HONDA`s FOUR-STROKE RACE HISTORY 1954 ~ 1981 by Joep

HONDA's FOUR-STROKE RACE HISTORY
1954 ~ 1981
by
Joep Kortekaas
PITTSBURGH, PENNSYLVANIA 15222
The contents of this work including, but not limited to, the accuracy of events, people, and places depicted; opinions
expressed; permission to use previously published materials included; and any advice given or actions advocated are solely
the responsibility of the author, who assumes all liability for said work and indemnifies the publisher against any claims stemming from publication of the work.
All Rights Reserved
Copyright © 2010 by Joep Kortekaas
No part of this book may be reproduced or transmitted
in any form or by any means, electronic or mechanical,
including photocopying, recording, or by any information
storage and retrieval system without permission in
writing from the author.
ISBN: 978-1-4349-8083-4
eISBN: 978-1-4349-4324-8
Printed in the United States of America
First Printing
For more information or to order additional books, please contact:
RoseDog Books
701 Smithfield Street
Pittsburgh, Pennsylvania 15222
U.S.A.
1-800-834-1803
www.rosedogbookstore.com
Dedicated to
the late SOICHIRO HONDA
whose genius made it all possible,
and
my wife Keiko and daughter Petra,
the women in my life.
3
CONTENTS
Foreword . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
Acknowledgement . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
The Early Years . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
The "Golden Age", 1959 – 1967 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
• June 1959, Isle of Man . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
• Copies? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
• The 250 cc four . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
• Early Production Racers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
• General information on Honda racing motorcycles . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
1960 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24
1961 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32
1962 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41
1962: Honda sidecar record . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 59
1963 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 60
1964 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 62
1965 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 67
1966 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 75
1967 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 86
1968: Honda goodbye . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 96
The riders . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 97
A matter of handling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 102
The RSC Hondas . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 107
Hondas at Daytona . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 116
Honda's endurance racing 1976-1981 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 122
1976
1977
1978
1979
1980
1981
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 122
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 128
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 131
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 133
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 136
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 139
The NR500 story . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 141
Appendix 1: Ways to increase power . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 153
Appendix 2: Inertia and pulsation effects . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 159
Appendix 3: Honda Grand Prix results per year . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 162
Appendix 4: Data of Honda racing motorcycles . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 167
Bibliography . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 175
Index . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 176
5
Foreword
A lot of books have been written about the Honda Corporation and its motorcycles,
and most of them mention the Honda racing motorcycles. A number of those books
give some information on the results of the Honda racing efforts, sometimes giving
some technical information about the racing bikes, but, to my knowledge, there has
never been a comprehensive history of Honda's racing exploits, comprising both race
results and the technical specifications (as far as they are known) of the works’ racers.
This situation is remarkable, since the Honda racing machines impact on the Grand
Prix racing of the 1960s has been profound. Their influence on the racing scene of the
time and on the development of four stroke engines – not only as regards motorcycles,
but also on the Formula 1 car designs – was unlike anything before it. This book
intends to give the reader a look back at those exciting days, with descriptions of
some Honda works’ racers that have never been published in Western magazines or
books before.
I have omitted the Honda two-stroke racers of the years after 1981 on purpose – from
the reactions of many people I gathered that most of them were far more interested in
the four-stroke racers of yore than in the later two-strokes. I have also omitted the
racing efforts with the so-called "Superbikes" in the USA – however interesting they
were, they were not international and almost entirely confined to that country.
Ing. Joep Kortekaas
Johor Bahru, January 2010
Acknowledgement
The writing of a book like this can hardly be accomplished on the basis of one
person's knowledge and information alone. Although I lived through all the years of
Honda's "Golden Age" and always gathered as much information as possible in those
days, still a lot of information for this book had to come from outside sources.
I wish to especially thank Jim Redman, MBE, who was kind enough to pre-read parts
of the book and to give his invaluable comments and encouragement; thanks also to
Mr. Sadao Tsujimoto of the Honda Corporation, who kindly permitted me to use
pictures from the Honda Collection Hall, and Mr. Ozaki Mitsuo of the Honda
Collection Hall, who admitted me in the restoration workshop, let me take pictures
there and answered patiently my various questions. I thank my dear friends Jan
Keessen from Holland and Ian Munro from Australia for their help. And last but
certainly not least, I thank my wife Keiko for her help in translating Japanese texts.
I have tried to give credit for the pictures in this book whenever I could find the
source – but many of these pictures are now between some 40 and 50 years old and
often of obscure origin, so it was not always possible to give credit where it was due. I
apologise to anyone whose name was not mentioned for the above reason.
7
HONDA's FOUR-STROKE RACE HISTORY 1954 ~ 1981
The Early Years
For most people, the Honda race history starts with the 1959 entry of the Honda team
in the Isle of Man TT. However, although practically unknown in Europe at the time,
Japan in those days had a fast growing motorcycle industry, but their models looked
very old-fashioned, and the ones that did look (more or less) modern were often
straight copies of German, British or American (read Harley Davidson – not that they
were so modern) motorcycles.
Honda, even back then already a very big motorcycle manufacturer, faced the
problem that it would be very difficult to sell its bikes worldwide. Japanese products
in general had a bad reputation regarding quality, based on Japanese pre-war products
(the budding camera industry in Japan faced exactly the same problem). So how do
you overcome such a problem? Easy – by proving to the world, that your engineering,
materials and fabrication methods and the products resulting from them are superior –
in the case of motorcycles by winning Grand Prix with them.
The story always goes, that Soichiro Honda had decided, in the beginning of the
fifties, that one day he would compete in the TT races on the Isle of Man. In reality,
this was not the case, although he had a keen interest in racing. However, when in
1953 business slumped, it was Takeo Fujisawa, the vice-president of the company but
in reality the real business leader, who urged Honda, in order to boost morale, to
declare to the workers that he would develop a racing bike to one day compete in the
famous TT races on the Isle of Man. Soichiro Honda, subsequently, made the
following declaration to his employees:
"Declaration
March 20, 1954
Some five years have passed since the founding of our Honda Motor Co., and I never
cease to rejoice that the efforts of all our employees have taken form in the
achievement of our epoch-making advances. Since I was a small child, one of my
dreams has been to compete in motor vehicle races all over the world with a vehicle
of my own making, and to win. However, before I can become victor over the whole
world, I must first, of course, assure the security of the business, obtain precision
machinery and equipment, and create superior designs. I have, therefore, been
devoting myself entirely to these points, and working to present superior practical
vehicles to our customers in this country. Consequently, I have not had any free time
for turning my energy to motorcycle racing until today. Now, however, reports on the
recent international motorcycle race held in São Paulo have provided me with detailed
information on the situation in the countries of Europe and America. I had thought
that I was seeing the world with a fair degree of realism, without being caught up in
fixed ideas, but now I realize that, after all, I have been blinded by my excessive
feeling for Japan in its present situation. Even now, the world is advancing at
tremendous speed. Conversely, however, as I have always felt, I am filled with an
abundant, unshakable confidence that I can win. The fighting spirit that is my nature
will no longer allow me to continue turning away. Now that we are equipped with a
production system in which I have absolute confidence, the time of opportunity has
arrived. I have reached the firm decision to enter the TT Races next year. Never
9
before has a Japanese entered this race with a motorcycle made in Japan. It goes
without saying that the winner of this race will be known across the globe, but the
same is also true for any vehicle that completes the entire race safely. It is said,
therefore, that the fame of such an achievement will assure a certain volume of
exports, and that is why every major manufacturer in Germany, England, Italy, and
France is concentrating on preparations with all its might. I will fabricate a 250 cc
(medium class) racer for this race, and as the representative of our Honda Motor Co., I
will send it out into the spotlight of the world. I am confident that this vehicle can
reach speeds exceeding 180 km/h. Even a superior aircraft engine has a power output
of about 0.55 PS per liter, but this racer will have nearly double that power, at 1.00 PS
per liter. (Honda meant, of course, 55 resp. 100 PS/l – note by the author) When this
engine is completed on the basis of our company’s creativity, it will be no
exaggeration whatsoever to say that it will rank at the worlds highest levels of
engineering. Since the motorcycle, a shining star of modern heavy industry, is a
comprehensive business, it will require the highest engineering level not only of the
engine but also of tires, chains, carburettors and other parts. To achieve this, it must
be supported by meticulous attention to detail and unremitting effort.
I address all employees!
Let us bring together the full strength of Honda Motor Co. to win through to this
glorious achievement. The future of Honda Motor Co. depends on this, and the burden
rests on your shoulders. I want you to turn your surging enthusiasm to this task,
endure every trial, and press through with all the minute demands of work and
research, making this your own chosen path. The advances made by Honda Motor Co.
are the growth you achieve as human beings, and your growth is what assures our
Honda Motor Co. its future."
In that same year, Fujisawa told Honda to visit Man to see the races for himself.
Honda came back, completely stunned by the power and speed of the European racing
motorcycles. He realised that there was no way he could develop a competitive racing
motorcycle with the parts available in Japan and within the year he mentioned in his
declaration and some time later he took a second trip to Europe, where he went on a
buying spree; he bought rev. counters, carburettors, rims, spark plugs and what have
you. A widespread anecdote tells, that, upon arrival at the Rome airport for his return
flight, his luggage was overweight and he was not allowed to check in. Since Honda
didn’t want to miss his plane, he opened his suitcases, took out all his clothing, put on
as much as possible on top of each other, including a heavy overcoat, filled his
pockets with parts, and said: "Now, how about it…. will it do?" "That will do", the
airport official said, whereupon Honda remarked: "What do you mean by saying ‘will
do’? Total weight is the same!”
Although a nice story, it’s highly unlikely that this dialogue ever took place: even ten
years later Honda’s English was very poor, and at that time one cannot believe that
Italian airport personnel would have been very proficient in English either!
In 1954 a 220 cc single-cylinder prototype racer was developed (see picture below).
10
A couple of years later, Honda had developed 250 and 305 cc twins with a single
OHC, used in national events (see pictures below).
Left: Dream SS CR70, 250 cc twin,
SOHC, 1957.
Right and below: C75Z, 305 cc twin,
SOHC, 1957. For some unfathomable
reason, Honda seemed to have a
strong liking for 305 cc engines i.s.o.
the normal 350 cc, and for a time
stuck with it for both street- and
racing bikes.
Also during the years prior to
1959, a 125 cc racer was
developed, the RC140. This was a
twin, with bore and stroke of 45 x
39 mm for a total capacity of
124.1 cc. The engine had two
overhead camshafts and two
valves per cylinder, with a
diameter of 26 mm for the inlet
and 24 mm for the exhaust.
Ignition was by battery and coil.
Its successor, the RC141, was also
11
a twin, but with a bore and stroke of 44 x 41 mm, which was to become a "standard"
for Honda. All other specifications were the same. From this bike the RC142 was
developed.
Racing in Japan differed markedly from European racing. There were no circuits as we knew them, and
most racing was done on unpaved roads, on volcanic ash of Mount Asama, using motorcycles with
high handlebars and semi off-road tyres.
By 1959, with the RC142, Soichiro Honda decided he was ready to take on the rest of
the world, and the first Japanese team arrived on the Isle of Man.
A legend was born.
12
The "Golden Age", 1959 – 1967
Photo Honda Collection Hall
13
inlet-camshaft. Lubrication was by wet sump system, carrying 2 litres of oil. The
gearbox contained 6 speeds, and the total weight of the bike was 87.5 kg. Tyre sizes
2.50 x 19 front, 2.75 x 18 rear. The wheelbase was 1265 mm.
The picture above shows the Honda mechanics in the Isle of Man, working on the
machines. In the background are a number of CB92 sports 125 cc road bikes, used by
the riders to get to know the circuit outside the official practice times. It shows the
very professional approach and determination of the Honda team.
In the TT, the bikes finished 6th (Naomi Taniguchi, picture below), 7th, 8th and 11th,
earning Honda the team price. Team leader Bill Hunt dropped his bike and didn't
finish.
The race proved that the
Hondas were reliable, but
not yet fast enough.
However, we have to bear
in mind that the Japanese
riders had never raced in
Europe, had probably
hardly ever raced on
paved roads, and were
confronted
with
the
mostgruelling circuit in
the world. Seen in that
light, the results were
outstanding.
After the race, the team
returned to Japan. Honda
16
spent on this one trip as much as most factories would spend on a whole season of
racing. It showed the world that they meant business, and that they could be expected
to be back.
Copies?
It is a well known fact, that Soichiro Honda was an admirer of German motorcycles,
and some of his early Benly production models showed a close resemblance to the
125 cc NSU Fox, while his early Dream models resembled early Zündapp
motorcycles. Maybe therefore it often has been written that the Honda 125 cc racers
were copies of the NSU
Rennmax twins (see picture
right). That, however, in my
opinion, is nonsense, and the
people saying it should know
better. Apart from the fact that
Honda in far away Japan had
absolutely no access to the very
secret data of the NSU racing
department, the Rennmax was
250, the Honda 125 cc; the
Rennmax had its bevel shaft
driving the inlet camshaft, the
Honda's shaft ended between
the camshafts. The NSU had a
360 degrees crankshaft, the Honda a 180 degrees one. The NSU had coil and battery
ignition, the RC142 got its sparks from a magneto, and had four valves per cylinder
against the two of the NSU, which had dry sump lubrication whereas the Honda had a
wet sump. The NSU had its clutch on the left-hand side, the Honda on the right.
So – the only common
points were the bevel shaft
and gears, and they were not
identical, and the fact that it
was a four stroke twin. Well,
the slightly earlier Simson
250 cc racers from EastGermany and 250 cc
Mondial racers from Italy
had the same characteristics
(bevel shaft and gears, fourstroke twin), and nobody
ever called them NSU copies. Furthermore, there are only so many ways in which you
can drive camshafts, and, with Honda a relative latecomer on the racing scene, they
had all been deployed one way or another. Whatever Honda would have chosen as
distribution system would have been called a copy. It shows the bias against the
Japanese designs, which even now, 50 odd years on, still exists.
So, if somebody tells you that all Japanese motorcycles are mere copies, ask the
person where they copied their power and reliability!
17
The 250 cc Four
That same year, 1959, Honda announced that they had produced a 250 cc fourcylinder along the same lines as the 125 cc twin. See pictures below (photos Motor
Cyclist and J. Kortekaas).
The idea of a 250 four was not a new one: during 1939-40, Gilera, Bianchi and
Benelli had built supercharged 250 fours, the Benelli water-cooled, the Bianchi and
Gilera air-cooled. The outbreak of the war prevented the use of those bikes, and when
racing was resumed after the war, supercharging was banned, making them redundant.
It was only in 1960, one year after the Honda four was introduced, that Benelli again
fielded a 250 cc four (We’ll disregard, no disrespect meant, a couple of British homebuilt fours of the fifties).
The Honda
four,
designated the
RC160, had the
same
specifications
as the 125 cc
twin, but the
cylinders were
now upright
instead of
being inclined,
and the
ignition was by
battery with
four separate
coils. Claimed
power output
was 35 PS at 13,000 rpm, with the same maximum engine speed of 14,000 rpm
18
as the twin. The engine had a 5-speed gearbox driven through a dry clutch and
weighed 58 kg. It seems that, like the 125 cc twin, the engine started life with 2 valves
per cylinder, but was later changed to 4 valves. For more detailed information see
Appendix 4.
The cycle parts were nearly identical with the 125 cc twin, the wheelbase being longer
by 45 mm at 1310 mm, and the total weight of the bike was 124 kg.
The RC160 was never raced outside of Japan and, being often raced on unpaved
roads, was mostly shown without a fairing, with high handlebars, an air-filter box and
with semi-knobby tyres.
Early Production Racers
1959 was also the year that saw the introduction of two production racers.
The RC71 was a 250 cc twin with one overhead camshaft and two valves per cylinder.
19
See picture above (photo Honda Collection Hall). It was based on the CS71 street
bike, and had a bore and stroke of 54 x 54 mm for a total capacity of 247.3 cc. There
were two carburettors of 22 mm diameter, although the bike in the Honda Collection
Hall has only one. Lubrication was by dry sump system, with the oil tank incorporated
in the petrol tank. The gearbox contained four speeds. Ignition was by battery and
coil. Power output was given as over 24 PS at 8,800 rpm.
The frame was of the spine type like the previously described racers, with leading link
front- and swing arm rear suspension. This bike was mainly used in south-east Asian
countries, a.o. in the GP of Singapore in 1960. Although the bike had a "works" type
model number, Honda themselves declared the bike to be meant for "clubman" races.
The CR71 was a production racer with road going equipment, based on the 1957 C71
street bike. All specifications were the same as for the RC71, but the oil tank was now
centrally placed in the frame. See picture below (photo Honda Collection Hall). This
bike has the two carburettors. According to Honda, 40 of these bikes were built and
sold.
Remarkable is, that both these production racers had an air scoop on the front brake –
something conspicuously missing on the works four cylinder RC160. Honda
sometimes moves in mysterious ways….
20
General information on Honda racing motorcycles
All the Honda GP and production racing motorcycle models to be discussed from now
on till the end of 1967 had a number of things in common. They were all four strokes
with the engine perpendicular in the frame and, with the exception of the one-off
RC144 125 cc twin and RC112 50 cc twin (and maybe a prototype CR110 production
racer), all had four valves per cylinder; so the fact of four valves per cylinder will not
be mentioned every time again. Valves were operated by hollow, hard-chromium
plated tappets and closed by double coil springs. Valve clearances were set by
grinding a protrusion on the tappet. Combustion chambers of cast steel were cast in
the light alloy heads, a practice also used, e.g., on the CB450 street bike. They all had
dry clutches, primary gear drive and chain rear-wheel drive. The ignition, with the
exception of the RC160, was always magneto ignition – initially with low-tension AC
generators feeding external high-tension (HT) coils, after around 1964 transistorised
breakerless electronic low-tension generators feeding the coils. Oil pumps were
invariably of the gear type, except on the CR93 twin, which had a plunger type. Every
cylinder got its own carburettor.
Arrangement of the valves, with the thin separating wall between them.
In principle there were two types of crankshafts. The works' racers, i.e., those with the
RC designation, in general had no flywheels, the crankshafts consisted of mere
cranks, with counter weights to balance them – the mass of the gears, camshafts,
clutch housing etc. provided the "flywheels". The second type of crankshaft, the more
conventional type with integrated flywheels, was used in the production racers, the
models with the CR designation.
21
Honda racers were, especially with a view to their dominance, really simply built
motorcycles, and very easy to work on, and hardly any special tools were ever needed.
The horsepower mentioned is the horsepower at the rear chain wheel; the
dynamometer was sitting at the location of the rear wheel. It's the most logical place
to measure the power; contrary to the crankshaft power, it gives a true indication of
the power that's available for propelling the bike. This power is approximately 15 %
lower than the crankshaft power due to mechanical losses.
Honda gave the power for their motorcycles in PS (German: Pferdestärke = horse
power). The English horses are approximately 1.4 % stronger than the German horses:
1 bhp = 1.014 PS (or, 1 PS = 75 kgm/s, 1 bhp = 76.04 kgm/s).
The development of the Honda racers followed a certain pattern, going through a test
phase in three stages. First the lubrication system was checked, so that any part that
could suffer premature failure through a deficiency of oil could be supplied with a bit
more of it. Once that was found right, the heat generation and cooling was checked.
With a little bit of oil here and an extra cooling fin there, the engine could be made
thermally healthy. (That this was not always the case was shown a.o. during 1961 and
1962 by the 250 cc and 350 cc fours, which were overheating). The last stage was
measuring the power. If this was considered not sufficient, cam timing and/or
inlet/exhaust systems were changed (see Appendix 2), and the whole story started
again.
In general, with racing motorcycles, the maximum allowable engine speed is
approximately between 5 and 10 % higher than the speed for maximum power. For
very short periods, an even higher speed is permitted, e.g. during changing down.
The early Honda racers had aluminium tanks, seats, fairings and front mudguards. On
the works racers, the fairings were hand-beaten and unpainted on the outside, except
for the yellow stripe with the word Honda, and the racing numbers; the inside was
painted flat black. The fairings of the production racers were painted orange and
silver, and flat black on the inside too. Later versions were made of some kind of
plastic material. On some of the later racers (e.g., the 50 cc twins and the 125 cc
RC149), the tanks and seats were made of polyester.
The early racers
had 6 mm bolts
inserted into the
bolts, holding the
front forks legs
into the upper
yoke. This was to
easily adjust the
amount of oil in the
front forks. Later
these 6 mm bolts
were discarded. The
early racers also
had
friction
steering dampers with additional hydraulic steering dampers – on later racers the
friction dampers were no longer used.
22
On the early racers the brake and clutch levers were always mounted on the clip-ons
outside the fork legs, on the later racers they were either outside or inside the fork
legs. Later clip-ons were often hinged, to facilitate changing without having to
remove the top yoke of the forks.
Above: RC174, levers inside the fork legs (photo J. Kortekaas).
Right: RC181, levers
outside the fork legs
(photo J. Kortekaas).
The clip-ons were
always painted in the
color of the frame (i.e.,
black, except on the
red-framed CR110 50
cc production racer).
The tanks were invariably painted red with two silver stripes, as were the seats; on the
latter, the silver stripes were later omitted. The front mudguards were always painted
silver. On the production racers, the tanks and seats were silver, and the CR110 50 cc
production racer had a red frame.
On the early Hondas, the front fork legs could be placed either on the left- or the
right-hand side – they had the connections for the brake torque arms and the
mudguards on both sides. Later this practice was discontinued, and the fork legs had a
fixed position.
Initially, the exhaust systems were chromium plated – during the 1960 season this was
changed to black paint.
At an early stage, transistorised rev. counters were used, but due to reliability and
accuracy problems they were again abandoned, and from then on normal, mechanical
cable driven rev. counters were used, mostly Smiths but sometimes Honda ones.
A remarkable fact of all Honda work's racers was their reliability. No doubt, to a large
extent this was due to their low mean piston speeds, which only in four cases
exceeded 20 m/s (RC166, RC174, CR72 and CR77). More background information
on why Honda racing motorcycles were so successful in such a short period is given
in Appendix 1.
23
1960
Overview
When Honda returned to Europe in 1960, a lot had changed compared with the year
before. In the first place, instead of competing in only one race, all the Grand Prix
were contested. That this posed a tremendous challenge as regards organisation goes
without saying. That year, the whole planning for the plane-, ship-, train- and car
travel and organisation was done by Dutchman Moerkerk, managing director of one
of the then largest Dutch motorcycle shops, "Het Motorpaleis". The Honda team
consisted of twelve people, of which 6 racers, plus 22 bikes and thousands (one
source said 7000) kilogrammes of luggage. According to Mr. Moerkerk, the airfreight
within Europe alone cost some US$ 8,000, the direct cost for the European adventure
some US$ 60,000, excluding the transportation costs from and to Japan. An enormous
amount fifty years ago!
Next to the Japanese riders, Tom Phillis and Bob Brown were contracted to ride for
Honda, later joined by Jim Redman, the future six-times world champion on Hondas,
after Phillis crashed during practice for the Dutch TT at Assen. Also, some privateers
were provided with racers, e.g., Dutchman Jan Huberts, who, with a 7th place, was
fastest Honda rider in the 250 cc in Assen.
Unfortunately, Bob Brown fatally crashed at the Solitude in Germany.
In the 125 cc class, the MVs and MZs were still faster than the Hondas, and the world
champion was Carlo Ubbiali on the single cylinder MV, with Gary Hocking on an
MV second and Ernst Degner on MZ third. However, Honda ended up third in the
manufacturers' world championship behind those two marks. Best individual results
Jan Huberts (NL), fastest Honda 250 rider (7th) in Assen 1960
24
for Honda were fourth places for Redman in Monza and Assen.
In the 250 cc class, Ubbiali and Hocking on their MVs took first and second place in
the individual world championship, with Luigi Taveri on another MV in third place,
but in the manufacturers' world championship the result for Honda was better, with a
second place. Best results for Honda were a second place for Phillis in the Ulster GP,
just 2 seconds behind Ubbiali, and a second place for Redman in Monza.
125 cc RC143
The RC143 was a completely new bike from the RC142, the most conspicuous
change being the switch from leading link front suspension to telescopic front forks,
and although the frame type was still the spine type, practically everything else of the
cycle parts was new. The front brakes were changed from single sided two-leading
shoes to double sided single leading shoe. Tyre size 2.50 x 18 front and 2.75 x 18 rear.
25
flywheels – in reality there were merely cranks, with counter weights for balancing.
Also two different sizes for the gear wheels on the camshafts must be poetic license!)
See the crankshaft picture with the RC162.
In the above picture, the up-turned bell-mouths of the four Kei-hin carburettors and
the two remote mounted float bowls can clearly be seen. Later those carburettors were
changed to the concentric type with a straight-line inlet track as shown below (picture
J. Kortekaas), which also resulted in a shorter inlet length.
27
The valve angle was 76 degrees: 36 degrees for the inlet and 40 degrees for the
exhaust valves. Bore and stroke were still 44 and 41 mm.
There was a sixspeed gearbox and
the engine had wet
sump
lubrication.
Power output was
given as over 38 PS
at 14,000 rpm.
Maximum
torque
was 2.1 kgm at
12,000 rpm.
Total weight of the
bike was 128 kg
dry, top speed was
given as over 220
km/h. For more
detailed information
see Appendix 4.
Also shown in the pictures, on both the RC143 and the RC161 the attachment of the
footrests was on aluminium forgings, as also used on the CB72 street bikes and the
later CR93 street bikes and production racers. On later models this practice was
abandoned.
The picture above shows Tom Phillis in the Isle of Man with the RC161 and a
mechanic.
The caption with this picture (by
Jung) from "Das Motorrad" read
(translated from German): "They're
coming close to the front – and
many will look into these pipes!"
Well, that prophesy has certainly
come true!
Notice the Girling shock absorbers,
which were used next to the
Japanese ones, which worked well,
but had a much shorter life, maybe
due to the fact that the Japanese in
those days used fish-oil as
hydraulic medium!
28
Racing kits for the roadsters
In 1960, before Honda brought out their CR110, CR93, CR72 and CR77 production
racers, they marketed racing kits for the CB92 125 cc and CB72/77 250/305 cc bikes.
CB92
The racing kit for the CB92 (see picture below) was very extensive. Most important
part was the new cylinder head (price in 1960 approx. US$ 40), complete with new
valves (the exhaust valves were Stellite reinforced) and special valve springs, a new
camshaft with rev. counter drive worm and the drive mechanism itself. The new
pistons gave a compression ratio of 12 : 1, and had narrower rings to reduce friction,
at the expense of higher wear. The top ring was hard-chromium plated. There was
also a special cam chain tensioner, not shown in the picture. A rev. counter, which
fitted in the place of the speedometer was provided, together with the drive cable.
The standard carburettor was maintained, but the jetting was changed. A completely
new exhaust system with open reverse-cone megaphones replaced the standard
system.
Since saving weight
was important, the
starter motor was
removed
and
a
blanking plate was
provided.
The
alternator stator and
rotor were to be
removed, and some
parts were provided to
replace them (the ring shaped part under the right handlebar end to replace the stator,
29
and the ring with holes under the bars to replace the rotor, onto which the ignition
breakers cam was fitted – see picture above). A special set of ignition coils was
provided to give better sparks at high revolutions.
As regards the cycle parts, new suspension units for the swing arm front- and rear
suspension were included, and the front brake scoop should have its blanking-off plate
removed and a special grill fitted in its place. Dropped handlebars were provided, as
were rear-set footrests and ball-ended brake- and clutch levers.
The intention was to remove the rear mudguard. A special seat was part of the kit, but
is not shown in the picture. A new gearbox sprocket and a set of rear wheel sprockets
completed the kit.
The end result of the installation of the kit is shown in the picture below.
The fairing and aluminium rims are obviously "private" modifications.
The standard CB92 pushed out 15 PS at 10,500 rpm – no power figure was given by
Honda for the race-kitted version.
CB72 and CB77
For the CB72 and CB77 there were also special racing parts, although the kits were
less comprehensive than the kit for the CB92. This is understandable, since the
CB72/77 already had a rev. counter and the footrests could be easily moved
backwards (see picture below). An aluminium reversed gear change pedal was
available (giving one down, three up changes) or extended change rods were available
to be used with the standard steel gear change pedal, retaining the standard gear
change pattern.
Pistons giving 11 : 1 compression ratio were available, as were a special camshaft and
stronger valve springs.
30
Air filters for the carburettors were to be removed, and inlet bell mouths fitted. The
standard exhaust system was replaced with a system with open, reverse-cone
megaphones. There were also close-ratio four- and even five-speed gear clusters. A
very extensive set of drive- and rear wheel sprockets was available. The starter motor
was removed, as was the alternator (although some people used the alternator as a low
voltage magneto for the high-tension coils), and a blanking plate was supplied for the
starter motor opening. Furthermore (steel) rims with narrower profiles (which of
course nobody bought, aluminium rims being the preferred option), special rear shock
absorbers and stronger, outside springs for the front forks were available.
Cycle parts were further changed with clip-on handle bars, a front forks top yoke
without the standard handle bar mountings, shortened clutch and throttle cables,
steering damper knob, racing tyres, a
special seat, and a shortened rear
mudguard with stays for a number
plate.
These modified CB72s were quite
successful in national races, and some
people even mounted a DOHC head
of a CB450 when they became
available in 1966! (see pic. below)
31
1961
Overview
1961 brought the great breakthrough for Honda. Next to Tom Phillis, Jim Redman,
Kunimitsu Takahashi, Sadao Shimazaki and Naomi Taniguchi, Luigi Taveri was
contracted. Furthermore machines were lent to Bob McIntyre and to a young, talented
rider by the name of Mike Hailwood. The bikes had been improved again, and the
combination of riding talent and fast, reliable machines brought Honda the individual
and the manufacturers' world titles in both the 125 and 250 cc classes. In the 125 cc it
was Tom Phillis who could just win ahead of Ernst Degner (MZ), with Taveri third. I
said "just", because, although Honda won 8 out of the 11 races, there were no team
orders and the winner was nearly every race a different one, while Ernst Degner kept
on collecting points. Phillis won the first GP in Spain, with Degner in second place,
Degner won in Germany where Phillis retired, Phillis won in France with Degner
second, Hailwood won the TT of Man, Phillis the Dutch TT, Belgium was for Taveri,
with Degner fourth, in East Germany it was Degner with Phillis second and Takahashi
third, the Ulster GP was for Takahashi with Degner second and Phillis third, Monza
was won by Degner followed by Tanaka (Honda), Taveri, Phillis and Redman,
Sweden was won by Taveri, ahead of Takahashi and Redman, Phillis came in as sixth
– Degner led the title chase with two points more than Phillis, and Argentina had to
bring the decision. However, Degner decided after Sweden to defect from EastGermany to the west, and had to find another machine to compete. He got an EMC,
but the bike arrived too late in Argentina and the title went to Phillis.
Phillis (26) and Hailwood, Honda 125 cc, Assen 1961
In the 250 cc class Mike Hailwood won the title, with Phillis second and Redman
third – a total Honda domination. The only GP not won by Honda was Spain, where
Gary Hocking won on an MV. However, for that race, the first of the season, the new
32
bikes were not yet ready, and hybrid machines (about which more later) with the old
RC161 engines were used.
Left: Mike Hailwood on his
way to give Soichiro Honda
his first Isle of Man TT win
on the 125 cc 2RC143.
If Honda appreciated the
fact that Hailwood won
against their works riders,
they really knew how to
hide it– after Hailwood's
wins in the 125 cc and 250
cc classes on Man, their
only reaction was to present
his father Stan Hailwood
with a bill for £ 200 for
transporting the bikes from
Japan…
The story goes, that Soichiro
Honda himself was so happy
with the first wins of his
machines on Man, that he
kept the winning 125 cc
Honda in his home, and later
donated the bike to Murray's
museum on Man. However,
that bike is definitely not
Hailwood's winning 2RC143,
but a dilapidated RC143 of
1960, the very same bike as
shown on page 25 as
photographed earlier in Holland, complete with the same dents and holes in the
fairing. See museum picture above. They didn’t even get the logo on “Hailwood’s”
helmet right…To paraphrase a saying, there are lies, damn lies and originality claims!
125 cc RC144
The RC144 (see picture right) was an
experiment by Honda, and one of the few
racers that was a flop. It had a long stroke
engine with a bore and stroke of 42 x 45
mm, with the cylinders inclined under 10
degrees, and with two valves per cylinder.
The engine had wet sump lubrication and a
six-speed gearbox. Claimed output was 22
PS at 13,000 rpm. It was only raced once,
in the German GP, and, after that, went
straight back to Japan. One still exists in the Honda Collection Hall. Honda
33
themselves once called it an "unfortunate" bike. However, the interesting and most
important thing is, that it clearly showed that the days of long-stroke engines and twovalve heads were definitely over.
125 cc 2RC143
The bike that was used in all other races during the season was the improved version
of the RC143, the 2RC143. Gone was the spine frame to make way for an open,
double loop frame, with a tube arrangement around the steering head not unlike that of
the Norton Featherbed frame. See pictures below.
The engine was identical with the RC143, but the Keihin carburettors were concentrics with cylindrical slides.
Compression ratio was still 10.5 : 1. Six-speed gearbox.
Power output was 23 PS at 14,000 rpm. Dry weight was
97 kg.
Big bore black hose is the
crankcase breather. The
125s were raced this year
mainly without the front
mudguards.
2RC143
250 cc RC162
As with the 2RC143, the spine frame had gone, and the new frame was also of the
open, double loop type. The frame tubes did not have the same diameter everywhere;
where they joined the steering head, they tapered out to a larger diameter - a very
34
sophisticated (and expensive) way to increase strength and rigidity. Material of the
frame tubes was chromium-molybdenum steel. The bikes were raced with double
sided, single leading shoe brakes, although the picture below shows a double twoleading shoe brake. Tyre size 2.75 x 18 front and rear.
The engine was further developed and although compression ratio (10.5 : 1), valve
angles (36 degrees inlet, 40 degrees exhaust) and bore and stroke (44 x 41 mm) were
still the same, it delivered 45 PS at 14,000 rpm. The pistons were cast alloy, and the
piston rings made of a specially developed cast iron – the top ring was hard-chromium
plated.
The cylinders were inclined 30 degrees, and the engine was 80 mm narrower, and to
improve aerodynamics no longer had the wet sump – the oil was carried in a tank
under the seat. This latter move was in the first instance not a great success, the bikes
suffered from overheating.
Picture left shows Bob McIntyre in Assen
with his sponsor, famous ex-racer Reg
Armstrong, who’s cutting holes in the lower
fairing to increase cooling of the engine of
the 250 four. Two rubber hoses led from the
round holes in the front of the fairing to the
space behind the carburettors to provide the
latter with large quantities of cool air. This
was a typical McIntyre modification – most
of the racers he rode, including the Bianchi
twins, had this.
35
The picture above (photo Ian Munro) shows the crankshaft – just some 280 mm long.
There are no flywheels, just bob weights for balancing. The main bearings are held in
steel clamps, which bolt straight to the upper casing, which gives a very strong and
stiff construction. This same construction is used in almost all Honda work's racers
(and was also used in the first CB450 four-speed street models, but was regrettably in
later models abandoned because of the higher cost).
Picture above (photo Ian Munro) shows the upper crankcase half with cylinders
(liners removed). Clearly can be seen that the camshaft drive is moved backward to
bring the inner cylinders closer together.
Some interesting data: diameter of the inlet valve head was 19 mm, exhaust valve
head was 17.5 mm, and shaft diameter of both valves was 4.5 mm. Lift of the valves
was 5.0 mm for the inlet and the exhaust valves. Picture below shows the form of the
cams, which are very narrow. Ignition timing was 52 to 55 degrees btdc, fixed.
36
Total weight of the bike dry was 105 kg, race ready 120 kg. For the absolute top speed
Honda mentioned 250 km/h; in fifth gear 220 km/h was reached.
An amazing fact about Honda was, that they were nearly always very "open" about
their racing motorcycles. Where other factories, especially the Italians, did their
utmost to prevent pictures being taken of their bikes, covering them up with sheets
and even reverting sometimes to strong arm tactics (which I for one have never
understood – as though you could read the secrets of an engine by merely taking a
picture of it…), Honda simply published information, pictures, exploded views and
ghost views of their bikes and engines, and let people like Jim Redman and Luigi
Taveri take the bikes home on a private basis, where anybody could have taken them
apart and study their construction, cam timing etc. A number of those bikes never
returned to Japan and are now in various private hands.
37
38
Exploded view of the RC162 engine, published by Honda themselves.
39
Hybrids
As mentioned before, the first GP of the season was raced with hybrid 250 cc fours.
When the racing season opened, the new RC162 engines were not yet ready, but the
cycle parts were. So
Honda
built
a
number of hybrids
with the new frames
but the old engines,
and sent their works
riders to the Italian
and Spanish spring
races to get used to
the handling of the
bikes.
When the new
engines were ready,
complete
new
RC162s were sent
to Europe, and the
hybrids were given to some selected Honda importers to be used by promising young
talent in national races. One of those young men was Kel Carruthers, in 1969 to
become world champion 250 cc on a Benelli four.
One of those hybrids ended up in Switzerland and is now in the possession of a Dutch
collector. The picture above shows the bike during restoration work (photo J.
Kortekaas).
Visit by Mr. Honda
Mr. Soichiro Honda himself has, as far as I
know, only once visited a Grand Prix in Europe
– he's here seen with his spouse in front of the
Honda pits at the Monza Grand Prix. It must
have been a happy day for him – in both the 125
and 250 cc classes his machines took the first
three places!
40
1962
Overview
For 1962 a new class was introduced for the world championship races: 50 cc, and
Honda decided to participate. Furthermore they participated in the 350 cc class. In the
50 cc they were not successful, the two-strokes were simply faster, but the other three
classes yielded three individual world titles and three manufacturers’ world titles. The
works riders for 1962 were Redman, Phillis, McIntyre, Tanaka, Takahashi and
Tommy Robb. Phillis crashed fatally during the 350 cc race on Man while in pursuit
of the MVs of Hocking and Hailwood. This caused Hocking, a personal close friend
of Phillis, to stop motorcycle racing. He returned to Rhodesia, and was ironically
killed when practicing for a car race, which he considered safer than motorcycle
racing. Later in the season Bob McIntyre was killed on a Norton in a crash during a
national race in England.
Redman (2), McIntyre, 350 cc TT of Assen. In the distance Stastny (Jawa) and Hailwood (MV)
The only 50 cc race won with the Honda 50 cc single was Finland, with Taveri first
and Robb second; the world title was won by Ernst Degner on Suzuki, Hans-Georg
Anscheidt was second with Kreidler, and Taveri came in third.
The 125 cc title went to Taveri, with Redman and Robb in second and third place. The
250 cc world title was for Redman, with McIntyre second, and the 350 cc crown was
also for Redman, with Hailwood (MV) second, and Robb third.
41
1962 TT of Man, 50 cc. Robb (8, Honda) leads Anscheidt (Kreidler)
50 cc RC110, RC111 and RC112
The RC110 (see picture below) was a single cylinder with a bore and stroke of 40 x
39 mm, dimensions which were nearly the same as those of most of its competitors.
The two overhead camshafts were driven by a gear train on the right hand side of the
engine. The cylinder was inclined 35 degrees. The valve angle was the same as for the
125 and 250 cc Hondas,
i.e. 36 degrees on the
inlet and 40 degrees on
the exhaust side. Ignition
was
by
crankshaft
mounted
low-tension
generator and HT coil,
with the contact breaker
points mounted on the
inlet camshaft.
Compression ratio was
the by now well-known
10.5 : 1 and power output
42
was 9.5 PS at 14,000 rpm. Wet sump lubrication. The bike was developed together
with a street version, which explains the five-speed gearbox and a plugged kick-starter
shaft opening. This five-speed gearbox was already replaced with a six-speed cluster
when the first GP of the season was held. Carburettor 23 mm.
For the French GP, the bore was increased to 40.4 mm, (all little things help) which
brought the capacity to 49.99 cc.
The machines used on Man were designated RC111. One Japanese source mentions a
bore and stroke of 42.5 x 35 mm, for a total capacity of 49.7 cc. The engines had
redesigned crankcases, an eight-speed gearbox and the inlet length was greater, with a
long intake rubber (see picture above).
For Assen the bike was provided with a ten-speed gearbox, however, during the race
Taveri used the eight-speed version – in Finland he used a nine-speed cluster.
The last race of the season was held at Suzuka, and here the RC112 made its debut,
the one and only race in which it was ever deployed. It was a twin, with bore and
stroke of 33 x 29 mm, giving a total capacity of 49.6 cc. Contrary to normal Honda
practice, a 360° crankshaft was used, which was supported in three main bearings.
Power was given as over 10 PS at 17,500 rpm, torque was 0.45 kgm at 15,000 rpm.
There were 2 valves per cylinder. Ignition was by magneto and still worked with
contact breaker points(!), lubrication was with wet sump system, and the gearbox
housed a nine-speed cluster. Dry weight was 62.5 kg. Tommy Robb won the race, the
second 50 cc win of the season.
The picture above shows the bike as ridden by Tommy Robb (photo Honda Collection
Hall) – note the "Italian" looking front mudguard; the picture below shows the
"naked" bike. (photo Honda Collection Hall)
43
125 cc RC145
The RC145 was directly derived from the 250 cc four cylinder RC162, with the drive
to the camshafts now by a gear train, taken from the centre of the crankshaft. In
principle it was a four without the two outer cylinders. Bore and stroke were still 44 x
41 mm. The only difference with the four apart from the number of cylinders was the
lubrication system, which was wet sump. Power was 24 PS at 14,000 rpm. Dry weight
was 103 kg, and as top speed over 180 km/h was mentioned.
The picture above (photo J. Kortekaas) shows the engine – note the gear change pedal
with two positions to allow for bigger or smaller feet. The picture below shows an
RC145 being restored in Honda's restoration workshop in the Honda Collection Hall
(photo J. Kortekaas).
44
Mechanics working on the RC145 engine, which from this perspective looks very big
for a 125 cc engine!
45
250 cc RC163
The RC163 had some small changes, the most obvious one being larger cooling fins
for the cylinders. See picture above (photo J. Kortekaas). Internally the engine was the
same. Power output was 46 PS at 14,000 rpm.
350 cc RC170 and RC171
Honda
first
competed
in the 350
cc class on
Man with
a 250 four
cylinder
bored out
to 47 mm,
giving 285
cc.
The
bike
delivered
50 PS at
13,500
rpm. Later,
a
new
bike,
designated
46
RC171, with bore and stroke of 49 x 45 mm, giving a total capacity of 339.4 cc, was
developed, used for the first time at the Ulster GP. Power output was 56 PS at 12,500
rpm. Since there were some cooling problems, the bike got an oil cooler behind the
exhaust down pipes. Later, after some small changes, the engine was thermally OK,
and the oil coolers were taken off again.
The picture above (photo Mick Woollett) shows the RC171 attended to by mechanics;
the picture below shows a frog's view of the mighty engine.
47
Production racers
1962 was the year that saw the introduction of the Honda production racers, the 50 cc
CR110, the 125 cc CR93, the 250 cc CR72 and the 305 cc CR77.
50 cc CR110
The CR110 was, except for the colour scheme (red frame), virtually identical to the
first RC110, complete with five-speed gearbox and blinded kick-starter shaft hole.
Here, too, the five speed gearbox proved inadequate, and was changed to the eight
speed version. See picture above (photo J. Kortekaas). Contact breaker points were
now mounted on the right hand crankcase cover, forward of the clutch, i.s.o. on the
inlet camshaft. Bore x stroke 40.4 x 39 mm. The claimed power was 8.5 PS at 13,500
rpm, maximum torque 0.46 kgm at 11,500 rpm. Carburettor diameter was 23 mm. Dry
weight was 61 kg.
Picture left shows the spur gear drive to
the two overhead camshafts.
48
Picture above shows the valves, valve springs, valve spring retainers and collets, hardchromium plated tappets, and bronze tappet guides with their mounting screws of a
CR110. On the left the rev. counter drive and a camshaft side cover. On the tappets
the small protrusions which were ground to the required size to set the valve clearance
can be distinguished.
Right: CR110 cylinder
head,
showing
the
combustion
chamber
with its four valves and
central 10 mm spark
plug.
49
Picture above: On the left parts of the CR110 with the 8-speed gearbox, i.e., the
camshaft covers with their lugs for frame mounting, the camshafts themselves, the
cylinder, piston, inlet manifold and –rubber, contact breaker drive and tappets. On the
right hand side the same parts for the older 5-speed version. From the offset of the
camshaft covers can be seen, that the 8-speed version was wider than the 5-speed one.
The same parts as above, seen from another angle.
50
On the left-hand side cover and clutch of the 8-speed version, on the right-hand side
those of the 5-speed version.
All above CR110 parts pictures by Moto House Minegishi.
One Japanese source mentions a CR110 with a bore and stroke of 40 x 39 mm and 2
valves(!) per cylinder, inlet valve diameter was 23 mm and exhaust valve diameter 20
mm, lift for both valves 5 mm. Camshaft drive was with vertical shaft and bevel
gears. Carburettor diameter 20 mm. This was probably a prototype that never went
into production. For more detailed information see Appendix 4.
125 cc CR93
The CR93 was also derived from a street bike, hence the blinded kick-starter shaft
hole. See picture below. The twin had a bore and stroke of 43 x 43 mm for a total
capacity of 124.8 cc. Drive to the camshafts was by spur gear train on the left hand
side of the engine. Size of the inlet valves was 18 mm, that of the exhaust valves 17 mm,
and valve stems were 4.5 mm. Compression ratio was 10.2 : 1. Carburettor diameter was
22 mm. Ignition was by crankshaft-mounted generator with external HT coils; the contact
breaker points were mounted on the inlet camshaft. Wet sump lubrication, which, as an
inheritance from the street bikes, had a rotating oil filter on the crankshaft and a plunger
type oil pump. Oil content 1.1 ltr. The gearbox had five speeds, with ratios 2.00 – 1.43 –
1.23 – 1.08 – 1.00 : 1. The dry clutch had 2 times 7 plates.
51
Claimed power was 21.5 PS at 11,500 rpm, but it was a well-known fact, that most of
these little gems were more powerful than that.
The early types had a single sided 2ls 200 mm, the later types a double sided, 180 mm
single leading shoe front brake. Dry weight 109 kg. The CR93 was a very popular
bike, not only for its superb speed and handling, but also for its legendary reliability
and longevity.
The picture above shows the distribution drive side of the engine (photo J. Kortekaas),
the cover on the inlet camshaft houses the breaker points.
52
Exploded view of the
CR93 cylinder head.
Contrary
to
the
works’ racers, which
had the drive to the
camshafts between
the cylinders, the
production racer had
the spur gear drive on
the left hand side.
The rest of the
cylinder
head
followed the normal
Honda practice, with
the hard-chromium
plated tappets for the
valves working in the
bronze tappet guides.
The very simple, low-tension ignition generator, which was crankshaft mounted.
53
The picture above shows the CR93 street bike from which the production racer was
derived. According to the parts list of this model, many parts, like the aluminium tank
(capacity 10 ltr), megaphone exhaust system, clip-ons, racing seat, forks upper yoke
etc., were available to turn the street model into a production racer. One of those
modifications can be seen in the picture below – this bike still has the steel rims and
combined speedometer/rev. counter of the street model, and the frame still has the
battery carrier. The megaphone exhausts are chromium plated, later types had
blackened systems. As can be seen, the generator- and oil filter cover differ from the
later models. Furthermore, the model in the Honda Collection Hall has aluminium
rims. To restore one of those early models to original condition can prove to be a
daunting task!
54
250 cc CR72
The CR72 (see picture
left – photo Honda
Collection Hall) was a
twin with a bore and
stroke of 54 x 54 mm,
for a total capacity of
247.3 cc. Compression
ratio 10.5 : 1. Ignition
by crankshaft mounted
generator with external
HT coils and contact
breakers on the left
hand crankcase cover.
Wet sump lubrication.
Six-speed gearbox. Power output was 41 PS at 12,000 rpm. Some interesting data:
Pme was 12.1 barg. Primary drive ratio 3.31 : 1, gear ratios 1.843 – 1.454 – 1.200 –
1.078 – 1.000 - 0.965. Diameter inlet valves 23.6 mm, exhaust valves 22.0 mm, valve
lifts inlet 7.0 mm, exhaust 6.0 mm, valve overall length 100 mm, valve weight 26.9 g;
with spring retainers, collets, tappet and 1/3 of spring weight 79.6 g.
305 cc CR77
The CR77 was identical to the CR72, the only difference being a bore of 60 mm, and
a carburettor diameter of 31 mm i.s.o. 29 mm. Power was 47 PS at 12,000 rpm.
Those two types, the CR72 and CR77, remain something of an enigma. Contrary to
the CR110 and CR93, they were not developed from, or in parallel with, similar street
bikes. The only thing they had in common with the street bikes were their bore and
stroke, resulting in the strange capacity of 305 cc for the 350 machine. Furthermore
they came in a bewildering variety.
First the engines, which were identical, except for the bore. But, there were at least
two types of engine.
One type was rather smooth, with light alloy covers (see pictures above), the other
type more cluttered, with magnesium covers (see pictures – photos J.
55
The frames came in four types: the spine types akin to the ones used by the CR93, as
already shown; some types with twin front down tubes (see picture above – this bike
has the type 2 engine but no external oil lines); the open, double loop type as used on
the works racers (see picture above); and a kind of combination, with a central tube
under the tank, twin down tubes to the swing arm bearings, and twin front down
tubes. See picture below.
Roy Bacon, in his excellent book "HONDA – The Early Classic Motorcycles", states
that the CR72 and CR77 were derived from the factory twins CR250 and CR305,
which should be the ones with the type 2 engines. However, I've never been able to
find any reference anywhere else to those CR250 and CR305 types, and even the chief
Honda restorer in the Honda Collection Hall knew nothing about them. My own type
2 engine was simply stamped CR77.
57
CR72s and CR77s were, contrary to the CR110 and CR93, not sold to the public after
their introduction. They were used by the works riders during 1963, and from then on
were gradually dispersed. Allegedly a total of 40 of them were made. My own CR77
was left behind in parts and incomplete at Schiphol airport by the Japanese team upon
their return to Japan, and never picked-up – Dutch customs sold it afterwards.
So, why did Honda make these twins in the first place? Seemingly not to sell them to
the public. As a cheap alternative to the fours for the works riders? Hardly. The cycle
parts were nearly identical to those of the fours, so that would give no difference in
price – and to design, build and develop completely new twin engines with all the
necessary new dies, moulds and tooling would probably be just as expensive as
making a couple of spare four cylinder engines, or at least make a lot of spares. So,
again, why?
58
Honda Sidecar Records
On 4 December 1962, the well known sidecar racer Florian Camathias broke three
one-hour sidecar world records on Monza, using a 250 cc Honda RC163. Although
this was not an official Honda involvement, it is interesting enough to be mentioned
here. Camathias got the Honda on loan from the German Honda representatives in
Hamburg, with the stipulation, that apart from the fairing and the connection of the
sidecar, nothing was to be changed on the Honda. Camathias mounted a special full
fairing, and added a sidecar wheel, the outriggers of which bore a by the FIM
prescribed ballast weight of 60 kg. Total weight of the sidecar so became 73 kg, and
the total weight of the combination was 180 kg. See picture below.
During the attempt the weather was rather bad, and to top it all Camathias ran out of
fuel seven minutes before the hour was over! In an attempt to run back to the pits he
fell and got wounded in his face.
Nevertheless, he managed to break three records:
•
•
•
The record over 100 km for 250 cc at an average speed of 192.092 km/h,
which was previously held by Murit on a Moto Guzzi at 148.773 km/h;
The record over 100 km for 350 cc which was previously held by Milani on a
Gilera four-cylinder at 189 km/h;
The one hour record for 250 cc at an average speed of 173.037 km/h,
previously held by Murit on Moto Guzzi at 148.400 km/h. This average speed
was so much lower because of the lost 7 minutes; Camathias fastest lap was
199.123 km/h, so that, if he had been able to complete the full hour, he would
no doubt also have broken the one hour 350 cc record, which was held by
Milani on the Gilera four-cylinder at 187 km/h.
59
1963
In 1963 Honda reduced their
racing efforts a bit, because
over the last four years the
racing had been an enormous
drain on the company's
resources, and a lot of those
resources were now needed to
develop their Formula 1 car.
Honda retired from the 50 cc
class, and the works riders
Redman, Taveri, Takahashi and
Robb had to make do with last
year's bikes, plus production
racers. After the Ulster GP, the
mechanics and spare parts went
back to Japan, leaving the
works’ riders more or less like
privateers. (Picture right shows the Honda team on the Isle of Man, when the
mechanics and parts were still there).
Competing with last year's bikes, which for lack of parts and mechanics were
definitely not in first class
condition, showed in the
results. In the 125 cc class
the Suzuki two-stroke
twins were faster than the
RC145s and won 9 out of
the 12 races, giving Hugh
Anderson the title, with
Taveri
second
and
Redman third. In the 250
cc class Tarquinio Provini
with his fabulously fast
single cylinder Morini
gave Redman a run for his
money that was only
decided in the last round
of the championship,
which again went to
Redman, with Provini
second and Fumio Itoh
(Yamaha) third. Only in
the 350 cc class there were
no problems. Redman took the title, ahead of Hailwood (MV) and Taveri on a CR77
production racer.
The picture above shows Redman at the GP of Monza, chasing Provini who won at an
average race speed of 179.6 km/h.
The fact, that Honda still won the world championship in two of the three classes they
competed in, and were second and third in the class they didn’t win, with machines
60
that were last year's and were sadly lacking in maintenance, clearly shows the
superiority of the original designs, and the outstanding reliability and longevity of the
engines.
However, Honda realized during 1963, that their relaxed attitude would cost them,
and for the last GP of the 1963 season, in Japan, new machines were developed. For
the 50 cc class a new twin, the RC113, and for the 125 cc a new four cylinder, the
RC146, were developed, and for the 250 and 350 cc classes the existing fours were
further improved. Taveri won the 50 cc, but after having been fastest during practice
in the 125 cc, retired with ignition problems after the first lap. Frank Perris on the
Suzuki won, after he and Jim Redman had changed places for first place several
times, with Redman coming in second. A "photo-finish" had to decide the winner!
Those machines, in an updated form, were used during 1964.
Perris (14), and Redman during the 125 cc class in Japan. It's easily understandable,
that some people thought Redman was really too big for the 125s! The Honda is
remarkably small for a 125 cc four stroke 4 cylinder; compare it to the 125 cc Suzuki
two stroke twin.
61
When towards the end of the season it became clear, that Read was going to win the
250 cc championship, Honda unveiled a six-cylinder,
secretly developed for the 1965 season, ahead of time
in Monza. See picture left, showing Redman taking the
bike out for its first practice spin. Initially Redman led
the race easily ahead of Read, but then his six started
overheating and he had to relax the pace, whereupon
Read won and became the first world champion for
Yamaha. Redman was second and Alan Shepherd
(MZ) was third.
Afterwards Redman conceded that in principle it was
his own fault that the six started to overheat in Monza
during the race. During practice he had deliberately
held back, so as not to reveal the real potential of the
new six. However, would he have gone all out, the
overheating problem would have shown during
practice, and the mechanics would have been able to
do something about it.
The 350 cc class was again a walkover for Honda. Redman won all the races, and the
only man who could keep him more or less in sight was his protégé Bruce Beale on a
production racer CR77, who ended up second, while Mike Duff was third on an AJS.
50 cc RC113 and RC114
The RC113, (See pictures above and below – photos Honda Collection Hall)
introduced during the Japanese GP of 1963, was a twin with the same bore and stroke
as the previous RC112, 33 x 29 mm for a total capacity of 49.6 cc, but now with four
valves per cylinder. Total valve angle was 72 degrees, symmetrical: both inlet and
exhaust valves were under an angle of 36 degrees. Ignition was by a transistorised
breakerless system, with 8 mm spark plugs. The carburettors were again the flat-slide
63
type. This carburettor type builds shorter than the round-slide type, and the very high
engine speeds necessitated a very short inlet and exhaust length to achieve optimum
wave tuning (see Appendix 2) Lubrication was by wet sump, and there were nine
speeds in the gearbox. Power output was 13 PS at 18,500 rpm; the red line on the rev.
counter was at 19,000 rpm, and short excursions to 20,000 rpm were allowed. Dry
weight of the bike was 53 kg, lower than its predecessor through extensive use of
magnesium, and a curious front brake. The latter was the same caliper brake as used
on a normal bicycle, with two brake pads being clamped on to the rim. This saved
total weight and unsprung weight, which improves handling. Two large, light alloy
discs were mounted on the wheels to give some streamlining.
The RC114 was practically identical with the RC113, with the gear train to the
camshafts on the right-hand side of the engine and a bore and stroke of 33 x 29 mm
for a total capacity of 49.6 cc. Valve angle was also the same with 36 degrees for both
inlet and exhaust valves. Power output was 14 PS at 19,000 rpm, red line was at
20,500 rpm and short time excursions to 23,000 rpm were permitted. There was a
nine-speed gearbox. Top speed was well over 170 km/h.
125 cc 2RC146
The type designation 2RC146, starting with a 2, would suggest that there has been a
type RC146, of which this was the improved version. Nothing is actually mentioned
anywhere about an RC146 (although one Japanese publication gives a picture,
unfortunately with mounted fairing), but reading between the lines in the Japanese
texts, the RC146 was the bike that was used in the Japanese GP of 1963, and the bikes
then used afterwards during the 1964 season were the types 2RC146.
64
The engine was a smaller version of the 250 four (see picture above, photo Mick
Woollett), with the gear train to the camshafts from the centre of the crankshaft. Bore
and stroke were 35.26 x 32 mm for a total capacity of 124.99 cc. Ignition was by a
transistorised breakerless system, with 8 mm spark plugs as on the RC113. Power
65
output was 28 PS at 16,500 rpm, red line at 18,000 rpm and short time allowable
maximum was 19,000 rpm. An eight-speed gearbox was fitted to keep the engine
within its narrow power band.
250 cc RC164, 2RC164 and 3RC164
The RC164 four was a little bit lower and lighter than its predecessor RC163. Power
output was increased to 48 PS at 14,000 rpm with the red line at 15,000 rpm. Power
increase was attained, a.o., by using slightly larger inlet valves. Ignition by electronic,
breakerless system. Later a version with 49 PS at 14,500 rpm, the 2RC164, was used.
Maximum allowable engine speed was 15,500 rpm. No further changes were
mentioned.
The 3RC164 was a six cylinder with the same configuration as all the other Hondas.
Bore and stroke were 39 x 34.5 mm for a total capacity of 247.3 cc. Ignition was by a
transistorised breakerless system, with 8 mm spark plugs. Lubrication was, contrary to
the fours, by wet sump. The gearbox was a seven speeder. Power was 54 PS at 17,000
rpm. A top speed of more than 240 km/h was claimed.
Although a six cylinder, the bike was very narrow, not wider than the RC161, and the
six megaphones were neatly tucked away to give maximum cornering clearance.
350 cc RC172
The main change of the RC172 from its predecessor was a new bore and stroke of 50
x 44.5 mm, changing the total capacity from 339 to 349.3 cc. Power output was 58 PS
at 13,000 rpm, with a red line of 13,500 rpm. No further changes.
500 cc RC180
During the 1964 season a new racer for the 500 cc class was developed, the RC180.
This bike was based on an enlarged 350 cc racer. It was a four cylinder with bore and
stroke of 54.6 x 48 mm, which gave a total capacity of 449.5 cc. Compression ratio
was 9.8 : 1, and developed power was given as 67.8 PS at 12,000 rpm; maximum
torque was 4.28 kgm at 9,500 rpm. Diameter of the carburettors was 28 mm. Wet
sump lubrication system. For more detailed information see Appendix 4.
With 67.8 PS at the rear wheel, this engine must have developed some 79 PS at the
crankshaft, compared to the approximately 70+ PS of the reigning MV 500 cc four,
raced to the world championship 1962, '63, '64 and '65 by Mike Hailwood. However,
Honda might have considered the power difference not enough.
Whatever the reason, as far as is known, this bike was never raced.
66
1965
Overview
1965 proved to be a year of mixed results. The Honda Research & Development
Company (which covered the racing department, said to have contained at that stage
some 400 engineers, technicians and mechanics) was still heavily involved in the
development of the Formula 1 car, and the motorcycles might not have got the amount
of attention they needed. After Francorchamps, halfway through the season, the
mechanics returned to Japan and the care for Redman's bikes was left to Nobby Clark.
The works riders that year were Jim Redman, as usual also acting as team captain,
Luigi Taveri and Ralph Bryans.
Honda skipped the first GP of the season, Daytona, where Suzukis won the 50 and
125 cc classes, and Read on the Yamaha the 250 cc. In the end, it made no difference
for the results.
In the 50 cc class, Hondas won 5 of the 8 rounds, and Bryans became world
champion, with Taveri second and Anderson (Suzuki) third. Honda also won the
manufacturers' title.
The 125 cc class was a total disaster that year. Honda started the season with last
year's 2RC146; they retired in Germany and Spain and ended up down the field in
France.
There is really no explanation why these bikes, which were so superior during the
previous season, were all of a sudden so down on performance and reliability.
Luigi Taveri on the 2RC146 in France. After initially leading the race, he slowed and subsequently
retired.
On the Isle of Man, the 4RC146 made its debut. Taveri came in second in Man, the
best place of the season(!), and came in 5th in Holland. In East Germany and
67
Czechoslovakia the Hondas didn't start, in Ulster Bryans finished 4th, in Monza again
no Hondas. In the last GP of the season in Japan, the new 5 cylinder 125 cc was
unveiled, and though the bike was streets faster than the Suzukis, Taveri had to reduce
speed while leading because of an oil leak, and finished second.
Hugh Anderson (Suzuki) became world champion, with Frank Perris (Suzuki) second
and Derek Woodman (MZ) third.
In the 250 cc and 350 cc classes, it was Jim Redman who had a disastrous season. No
start in Daytona, in Germany he fell off the 350 in the rain while chasing Agostini on
the new and very fast 3 cylinder MV and broke his collarbone, which prevented his
start in the 250 and his participation in Spain. In France Redman retired in the 250
with gearbox trouble while leading from Read. On Man everything went well, and
Redman won both the 250 and the 350 cc ahead of Read (Yamaha).
In Assen, in the 250 it was Read ahead of Redman, in the 350 Redman ahead of
Hailwood (MV).
Assen, 350 cc: Redman with Hailwood in tow.
In Belgium the 250 was for Redman, Read was second, and it was the same in East
Germany, where Redman also won the 350 cc.
In Czechoslovakia in the 250 Redman came in third behind Read and Duff (Yamaha),
he won the 350. In Ulster Redman fell off in the 350 and broke his collarbone again,
and again it prevented his participation in the 250, which was duly won by Read.
Honda subsequently informed Redman that there would be no bike for him at Monza,
so Redman stayed home in Rhodesia. Later it transpired that there was a bike waiting
for him at Monza – a mighty Honda blunder. In the 250 cc class Read used here for
the first time a four cylinder Yamaha. All this bad luck for Redman brought Agostini
68
Sachsenring, East-Germany, start 250cc. 140 Mike Duff (Yamaha), 139 Phil Read (Yamaha), 129 Jim
Redman, the eventual winner.
on the MV, who won easily in Finland and Italy, so close in the 350 cc class, that the
last GP in Japan had to bring the decision. When Redman put his goggles on for the
decisive 350 cc race on the Suzuka course, a bee slipped in and stung him over his
eye, which swelled completely shut. To make matters worse, only 4 of the 6 speeds of
his bike were home. But a contact breaker spring (of all things!) of Agostini's MV
broke, and Redman came in second behind Hailwood (MV) which was enough for the
title, while Mike Hailwood won the 250 on a Honda six. Read became 250 cc world
champion, with Duff second and Redman third, Honda was second in the
manufacturers' world championship. In the 350 Redman was world champion, with
Agostini second and Hailwood third.
Mike Hailwood, for the first time on a Honda six, winning the 250 cc in Japan
69
Picture left (photo J.
Kortekaas) shows the
left side of the engine
with
the
electronic
ignition magneto. It also
shows the extensive use
of
magnesium
–
everything that's colored
bronze-brown
(for
colour picture see front
cover).
During the season, both high level exhausts and the normal
low level exhausts were used. The high level exhausts had
the advantage of a smaller frontal area, because the fairing
could be kept narrower (see picture right, photo J.
Kortekaas), which gave less air drag.
125 cc 4RC146 and RC148
The 4RC146 was an improved version of the 2RC146, and nearly identical to it – the
only external difference was the shorter exhausts of the 4RC146. Power was raised to
30 PS at 17,000 rpm. In actual practice, the engine hardly ever ran well, with
continual carburation and ignition problems. This is really amazing – the other bikes,
including the six cylinder, hardly ever had these kinds of problems.
Some interesting data: the piston, as usual for Honda with two compression rings and
one oil scraper ring, weighed 34 g without the pin and rings. The pin, with a diameter
of 11 mm, weighed 11 g. An inlet valve had a head diameter of 14.5 mm and a stem
diameter of 3.8 mm and was 74.4 mm long. Weight: 9 g. Two valve collets and the
retainer weighed 1 resp. 3 g. Nobby Clark said they used tweezers to put the Honda
valve gear together.
The RC148 was the great surprise of 1965 (see picture below). It was a five cylinder,
in principle two and a half 50 cc twins. Bore and stroke were 33 x 29 mm, for a total
capacity of 124 cc. Drive to the camshafts was by gear train between the third and
fourth cylinders. Power was 34 PS at 20,000 rpm. There were eight speeds in the box,
and the engine had wet sump lubrication.
71
The four exhausts of cylinders 1, 2, 4 and 5 sat in the normal place, left and right of
the bike, the exhaust of cylinder 3 swept up and around the left hand side of the
engine, crossed through the frame, to end up under the right leg of the rider. See
picture below.
Dry weight was given as 85 kg.
72
250 cc 3RC164 and RC165
The six cylinder, used in the Monza GP of 1964, was called the 3RC164 – a strange
name, because the RC164 part refers to the four cylinder. The same bike was used in
the beginning of 1965 (see picture below – photo Volker Rauch). It had two three-
cylinder crankshafts, coupled in the centre of the engine. The general construction of
the engine followed the usual Honda practice. Bore and stroke were 39 x 34.5 mm, for
73
a total capacity of 247.3 cc. Valve
angle was 75 degrees, 34 degrees on
the inlet and 41 degrees on the exhaust
side. Spark plug size was the by now
familiar 8 mm. Of course the ignition
was by transistorised system – since
1964 the contact breakers were
obsolete on Honda racers. Lubrication
was by wet sump system – there was an
oil temperature gauge. The gearbox
contained a seven-speed cluster. Picture
left (photos left and above Volker
Rauch) is a bird’s eye view, showing
the narrowness of the engine. The black
cylinder sticking-out on the right is the
catch tank for the engine breather.
The RC165 was, apart from some
details (e.g., bore and stroke 39 x 34.8
for a total capacity of 249.43 cc, see
Appendix 4), identical to the 3RC164,
but power output was raised from 54 to 56 PS at 16,500 rpm, with a red line at 17,000
rpm – short excursions to 17,500 rpm were allowed.
One Japanese source mentions a 2RC165, used in 1965, and a 3RC165 used in the
beginning of 1966. All data of these types are the same as for the RC165, so the
changes must have been in small details.
350 cc 2RC172
The 2RC172 was practically identical to the RC172, with detail modifications.
Although the basic design was then already several years old, the new MV-3 was still
no match for it as regards speed and acceleration.
74
1966
Overview
1966 became the absolute top year for Honda. They won the manufacturers' world
championship in all five classes, for that year they also competed in the 500 cc class,
and individual world championships in three classes. It is a unique fact, a record still
standing today. Although during the years 1958-60, MV also won the manufacturers'
title in all the classes they contested, there were only four classes then – and the
competition of the MVs was weak, not to use the term non-existent.
That year Mike Hailwood, arguably the greatest motorcycle racer ever, joined the
Honda team as a works rider (his participation and resulting first world championship
250 cc in 1961 was as a privateer, with the Hondas on a loan basis). After Redman's
retirement, Stuart Graham, son of the famous Leslie Graham, joined the team to assist
Hailwood.
In the 50 cc there was fierce competition between Taveri and Bryans on their Hondas,
and Anscheidt, after the withdrawal of Kreidler, on a Suzuki twin. After the one but
last GP of the season, the Isle of Man TT (that year one but last because strikes in
Great Britain prevented the TT from being held in June as usual), all three riders had
26 points, and a chance of the title. Then it became known, that the Japanese GP that
year would not be held on the Honda owned Suzuka circuit, but on the new Fisco
course, whereupon Honda decided not to participate, and the individual title went to
Anscheidt.
In the 125 cc class, the competition for Honda that year came from Phil Read and Bill
Ivy on Yamahas, not from Suzuki. Taveri took the title, with Ivy second and Bryans
third. The manufacturers' title went to Honda, with Yamaha second and Suzuki third.
In the 250 cc class, Redman and Hailwood had to defeat the Yamaha four cylinders of
Read and Ivy. Although the Yamahas were slightly more powerful with 60 PS, the
"What are you doing, Jim?" Mike looks back, while Jim makes a belly landing in the Spanish 250 at
Barcelona.
75
combination of Hailwood and the Honda six was so superior, that Hailwood won the
first seven races and was already world champion halfway through the season. In total
he won 10 of the 11 races that year. The only race he didn't win was Ulster – with his
participation in the 350 and 500 cc classes, he would have exceeded the FIM limit of
500 km in one day, and so he skipped the 250, in which he was already world
champion.
Read was second and Redman, who broke his arm in Francorchamps and retired from
racing, was third. In the manufacturers' standing, Honda was first, followed by
Yamaha, MZ and Bultaco.
In West Germany it was Read who lost it in the 250 (photo Kirschner) – and Hailwood and Redman
finished 1st and 2nd.
In the 350 cc class, Hailwood won the title with six victories, Agostini was second
with three wins, and Renzo Pasolini (AerMacchi) was third. Honda won the
manufacturers' title, followed by MV Agusta, AerMacchi and Jawa.
The 500 cc became a different story. Redman, who had decided that 1966 would be
his last season, wanted to round off his career with a 500 cc world championship, so it
was agreed that Hailwood would concentrate on the 250 and 350 cc classes, and
Redman on the 500. The first Grand Prix, in Germany, Redman won, with Agostini
second. Hailwood couldn't compete, since the FIM regulations forbade a rider to
cover more than 500 km in one race day, and with Hailwood's participation in the 250
and 350 cc classes, he would have exceeded this. In Holland both Redman and
Hailwood competed in the 500 cc. Agostini initially led the race, with Redman and
Hailwood following. Hailwood overtook both Redman and Ago, and took over the
76
lead, but crashed. Agostini then built-up a lead of 22 seconds over Redman, but the
latter fought back and in the later stages Redman overtook Agostini and won.
And in Assen it's Mike, sliding out of the 500cc race (photo Volker Rauch)
In Belgium, one week later, Redman had been fastest in practice, one second faster
than Hailwood and over 6 seconds faster than Agostini, but, during the race, in
pouring rain, he aquaplaned, fell and broke his left arm. Hailwood, although missing
his top gear, built up a lead of over a minute over Agostini, until further gearbox
trouble forced him to retire, and Ago won. Agostini then had the best chances for the
world championship, with one win and two second places, while Hailwood had still
zero points. In East Germany again Hailwood retired. In Ulster all was well and
Hailwood won, and he also won the TT on Man. However, by now Agostini had
amassed so many points, that Hailwood had to win Monza to keep his championship
hopes alive. He led the race, but the Honda engine, normally a paragon of reliability,
blew up, and Agostini was crowned world champion. Honda took the manufacturers'
title, MV was second and Matchless third.
The duel between Hailwood and Agostini in Monza, which ended when Hailwood's engine blew-up
after Mike had taken the lead and made the fastest lap with 199.038 km/h.
77
Team captain Jim Redman sit relaxed, waiting for Nobby Clark and other mechanics
to finish work on the Honda in Francorchamps, Belgium. Stan Hailwood (with hat),
the father of Mike, watches.
During practice, Redman was the first to take a 250 over the "magic" lap speed of 200
km/h, with a lap of 200.552 km/h, 0.5 sec. faster than his team mate Hailwood. The
race was won by Hailwood, followed by Read (who set the fastest lap with 199.685
km/h) and Redman. At the time, journalists present had the impression that during the
race, Redman's Honda did not perform as it had done during practice.
78
50 cc RC116
Difference between the RC115 and the RC116 was a new bore and stroke, being 35.5
x 25.14 mm. Power output was 16 PS at 21,500 rpm. At the rear wheel! This means
some 18.8 PS at the crankshaft, 377 PS per litre and a Pme of 15.8 kg/cm2. As regards
PS per litre, this is a figure that has never been surpassed by any naturally aspirated
four-stroke engine on commercial fuel. It gives an idea of the level of four-stroke
technology over 40 years ago. This engine was the most advanced of all the Honda
engines.
Red line at 22,500 rpm. Carburettors had flat slides. The gearbox contained a ninespeed cluster. Dry weight of the bike was 58 kg.
The gudgeon pin had a diameter of 9 mm and weighed 6 g. The inlet valve head was
13 mm, the exhaust valve head was 11.5 mm, and the stems had a diameter of 3.5
mm. Weight of the exhaust valve: 6 g.
125 cc RC149
The RC148, used in the GP of Japan 1965, had the same bore and stroke as the RC
114, 33 x 29 mm, but the new RC149 got the same dimensions as the RC116: 35.5 x
25.14 mm (see picture above; photo Mick Woollett).
The crankshaft had a special configuration: the three-cylinder part had the crankpins
at 120 degrees, the two-cylinder part had the crankpins, in the usual Honda fashion, at
180 degrees. Both crankshafts were coupled together at the position of the camshaft
drive.
The valve angle was 56 degrees, 24 degrees for the inlet and 32 degrees for the
exhaust valves. Lubrication system was by wet sump, with two oil coolers in the sides
of the fairing.
There was also an oil temperature gauge. The oil temperature was checked, and the
coolers could be covered more or less to maintain the oil temperature within certain
limits.
79
The RC166 engine with all its parts (photo Honda Collection Hall)
81
Picture left the cylinder head, showing again the advantage of having the drive to the
camshafts behind the cylinders i.s.o. between them. On the right the split camshafts
with the jack shaft and the driving gears. On the jack shaft the worm for driving the
oil pump (see also previous page).
On the left valves, valve springs, valve spring retainers and bottom washers, collets,
tappets, bronze tappet holders with their mounting bolts, a spark plug and a piston
with gudgeon pin and rings. There were only two (compression) piston rings, to
reduce friction there was no oil scraper ring. On the right the set of Kei-hin
carburettors. Both flat slides and round slides were used, depending on the circuit.
On the left the seven-speed gear cluster, on the right the crankshaft with the usual
Honda construction. The crankshaft is constructed as two 3-cylinder shafts, with the
cranks at 120 degrees. (All photos on this page Honda Collection Hall).
82
The crankshaft of the six was a very complicated construction, composed of 12
components. See picture below.
To build it to optimum dimensions, weight and strength, the conrods came in three
different sizes. The big-end bearings became bigger closer to the middle of the
crankshaft, because there the forces are highest. The same holds for the main
bearings, which had a diameter of 24 mm in the middle, and 14 mm at the ends of the
crankshaft. The camshafts too were thinner at the ends than in the middle, for the
same reasons.
To save weight, various parts were made in titanium, a.o., most bolts and nuts, wheel
spindles, swinging arm pivot spindle, clip-ons, chain tensioners and brake levers.
Engine and camshaft covers, the tank filler cap and carburettors were made of
electron, an alloy of aluminium and magnesium.
The "naked" bike. Photo Honda Collection Hall.
83
350 cc RC173
The
RC173
was
a
completely
new
motorcycle,
developed
concurrent with the 500 cc
RC181. Both bikes were
virtually identical. External
difference: the RC173 had
round camshaft covers,
whereas the RC181 had
rectangular ones. The
engines had now wet sump
lubrication, with external
oil coolers like the RC149
and
RC166.
The
carburettors had cylindrical
slides. However, bore and
stroke were the trusted 50
x 44.5 mm of its predecessor, and the gearbox contained six speeds. The megaphones
had very pronounced reverse cones. Power output was 64 PS at 13,000 rpm. (photo:
Volker Rauch).
The frames had now bolted-on, twin front down tubes. The picture below (photo Mick
Woollett) shows the Japanese mechanics working on the bikes in the paddock in
Francorchamps.
500 cc RC181
What has been said above about the RC173, holds for the RC181. Bore and stroke
were 57 x 48 mm for a total capacity of 489.94 cc. Total enclosed valve angle was 75
degrees, symmetrical, so both inlet and exhaust valves were hanging under 37.5
degrees. See picture below (photo Volker Rauch).
84
There was a six-speed gearbox. Power output was 85 PS at 12,000 rpm, with a redline
at 12,500 rpm.
A weak point of the RC181 was its crankshaft – the press fit of the crankpins
sometimes gave way, causing the crankpins to change position against one another,
with disastrous results, a.o. the reason of Hailwood's retirement in Monza.
85
1967
Overview
This would be, for the time being, Honda's last year in Grand Prix racing. They pulled
out of 50 and 125 cc racing at the end of 1966. At the end of the 1967 season, Honda
withdrew from the other three classes. They had achieved what they had set out to do:
from a totally obscure and unknown company at the start of 1960, they had become
the biggest and best-known motorcycle manufacturer in the world. Yet, the decision
came unexpected – Hailwood and Bryans had already signed their contracts for 1968.
Moreover, there were rumours about new, exciting racers – a 50 cc triple, a 125 cc six
cylinder and a V8 for the 250 cc class.
Suzuki also stopped at the end of the season, and Yamaha followed one year later.
In the 250 cc there was a fierce, ongoing battle between Read and Ivy on the Yamaha
fours and Hailwood and Bryans on the Honda sixes, a battle that was only decided in
the last race of the season. The Yamahas had been improved and were lighter, lower
and more powerful – with 70 PS they had now some 10 horses more than the Honda
six. This was compensated by the fabulous riding of Hailwood, but on very fast
circuits, such as Francorchamps and Monza, the Yamahas had the advantage because
Probably one of the most famous racing pictures ever – it shows Mike at Clermont-Ferrand, leaning to
the limit. (photo Volker Rauch).
of their superior speed. Furthermore, Hailwood retired 5 times from races, something
that had not happened the year before. In Barcelona, the first race of the season, he
had a flat tire; In Germany he quit with ignition problems. In East-Germany Read had
trained no less than 7 seconds(!) faster than Hailwood – nevertheless Hailwood
managed to stay ahead of Read until he retired with a broken valve. In Finland Bryans
retired with gearbox trouble, and in Monza Hailwood's six developed lubrication
86
problems. During the last race of the season, in Japan, Hailwood's crankshaft gave
problems. He probably drove the six much harder than the year before.
Hailwood and Read both ended up with the same number of points, but Hailwood
won the title, for he had 5 wins against Read's four. Ivy ended up third. The
manufacturers' title went to Honda, followed by Yamaha, MZ and Bultaco.
During 1966, Mike had been complaining about the road holding of the fours, and
Honda decided to enlarge the 250 cc six, about which Hailwood had no complaints, to
Mike at the Isle of Man TT with the RC174.
give him a new weapon for the 350 cc class. With more power than the four and
nearly 20 kg less weight, the combination Hailwood and Honda six was so superior,
87
that Hailwood won the title by winning the first five races, and then handed the bike
over to Ralph Bryans, who gathered enough points during the rest of the season to end
up third in the world championship (see picture above; photo B. R. Nicholls).
Agostini was second with the MV. The manufacturers' title went to Honda, ahead of
MV Agusta, MZ, AerMacchi and Benelli.
The battle in the 500 cc class was between Hailwood and Giacomo Agostini with the
MV. Hailwood complained, that he had to fight two opponents: Ago and his Honda,
which, although it had a superb engine, had, according to Hailwood, very bad road
holding. At the end of the season, both riders had the same number of points and both
had 5 wins; Hailwood had two second placings, but Agostini had three seconds and so
became world champion, with Hailwood second and John Hartle (Matchless) third.
250 cc RC166
The RC166 of 1967 was the same bike as the one of the previous season. Pictures
below (photos collection J. Kortekaas) were taken in the paddock at Assen.
88
In the one but last GP of the season, in Canada, a new six cylinder appeared. It seems
this bike was clearly more powerful, and had a bore and stroke of 41 x 31.5 mm and a
smaller valve angle. I'll call this the RC166N. (Notice, that the RC174, which was
used during the whole 1967 season, had 41 mm bore from the beginning – the
development history of these sixes is not always completely clear).
350 cc RC174
The RC174 was the enlarged version of the RC166, the total cylinder capacity of
297.06 cc was achieved with a bore of 41 mm and increasing the stroke to 37.5 mm.
Compression ratio was 10.6 : 1. Inlet valve diameter was 16.5 mm, exhaust valve 14
mm. Carburettor diameter was 22 mm. Power output was 67 PS at 17,000 rpm,
maximum torque was 2.8 kgm at 16,000 rpm. For more info see Appendix 4.
RC174 (photo Honda Collection Hall)
500 cc RC181N
89
,
The RC181N (the "N", just as with the RC166, stands for the Japanese character
"arata" or "kai", which means something like: "Updated version") that year no longer
had the bolted-on sub-frame, and the megaphones had lost the reverse cones. Capacity
was increased to 499.6 cc by enlarging the bore to 57.56 mm; the stroke remained the
same at 48 mm. Power output was nearly 90 PS at 12,000 rpm, maximum torque was
5.23 kgm at 10,000 rpm.
Calculated for crankshaft power, this was the first time that engine power surpassed
the 100 PS mark.
According to Nobby Clark, the only nonJapanese mechanic in the Honda team, the
racing department prepared a special Honda
for the TT of Man, which produced a
staggering 99 PS – 114 PS at the crank!
One of the experiments to improve handling
was mounting the front wheel in excenters, so
the trail could be altered – it didn't bring
much. Dry weight was 151 kg; top speed was
given as more than 260 km/h.
Tire sizes 3.00 – 18 front and 3.50 – 18 rear.
RC181. Clearly seen is the magneto for the electronic ignition below the carburettors
(photo Honda Collection Hall)
90
RC181 engine on the bench. Clutch plates are large in diameter, but rather narrow.
Large oil sump.
Just above the sump are the connections for the oil coolers.
91
The lower crankcase half has been taken off, showing the crankshaft and the six-speed
gearbox.
Gear cluster and crankshaft removed, showing the jackshaft that drives the clutch.
Next to the large driven gear wheel is the drive to the camshafts and the ignition, next
to that the drive to the oil pump.
92
Crankshaft with the steel caps holding the main bearings. The right-hand crank has
been taken off. The circular holes in the steel caps are for the oil supply.
Cylinder head with camshafts, the bearings of which are also held in place with steel
clamps.
93
Split camshaft. The cams of Honda racers are remarkably narrow. On the left-hand
side the drive worm to the rev. counter.
The cylinder head with its combustion chambers. Again the inner cylinders are close
together thanks to the rearward situation of the camshaft drive.
Close-up of the valves. Nothing out of the
ordinary here.
Valve with valve springs, tappet and bronze tappet guide block (left).
All photos of the RC181 internals by Hans Weeke.
94
Nobby (real name Derek) Clark, working on an RC181 engine in the race garage at
Amsterdam, Holland, where Honda had their headquarters. In the centre team
manager Aika Michihiko, generally known as Aika-san. And you really need a lot of
oil to lubricate those high-revving beasts…
The mechanics, with Nobby Clark at left, during a quiet moment in the paddock of
Man. Normal working days for the mechanics were from 8:30 am till 10 pm, 7 days a
week, although when the need arose, workdays of 20 hours also happened… Salary
was £ 100 per month, tax free, and Honda paid hotel and traveling expenses.
95
1968: Honda goodbye
When Honda showed for the first time on the Isle of Man in 1959, nobody could have
foreseen the impact that this obscure Japanese manufacturer would have on the
motorcycle world in general and the GP racing scene in particular. They caused a
revolution in racing bike design, and paved the way for their Japanese competitors –
Yamaha and Suzuki appeared in 1961, followed in 1966 by Kawasaki and
Bridgestone. Year after year the number of cylinders rose to enable greater piston
areas and hence higher power output. Had they continued racing, we would no doubt
have seen a 50 cc triple, a 125 cc six, and a 250 cc V8. Alas, it was not to be. After
nine successful years, sixteen world championships and hundred and thirty-eight GP
victories, Honda had achieved their goal, and retired from GP racing.
Their influence on engine design was profound and cannot be over-emphasised. When
they arrived on Man with four-valve cylinder heads, the opinion was voiced that those
Japanese were a bit behind the times – four-valve heads had been used extensively in
Europe, and had shown no advantage over two-valve heads. But when Honda started
winning with that "outdated" construction, those voices from the European "experts"
were quickly silenced. Benelli was the first to take a leaf out of Honda's book and
converted their 250 cc four cylinder to four valves per cylinder – which gave them an
increase in power of 5 PS and made an end to the recurring valve breakage. They
were soon followed by MV Agusta and Jawa. The four-wheeled racing world
followed suit.
The specific power of the Honda racers, PS per litre, has, as far as I know, never been
surpassed by engines running on commercial fuel. Their actual power output should
be food for thought for those people who, taking an old standard Honda CB350 twin
or CB500 four, and putting in a number of tuning goodies, claim power that not only
rivals that of the Honda works’ racers, but often surpasses it! Hard to believe, to say
the least!
After 1967, Honda's race activities stopped, but on a much more modest scale, Honda
RSC, the Racing Service Club, continued making special parts, race kits and complete
bikes.
Gradually, the factory got involved again, leading to their participation in Daytona in
1970, and their ultimate re-entrance in the GP scene.
But that's another story.
96
The Riders
The Honda "Golden Age" story would not be complete without a portrait gallery of
the various riders who helped Honda to their successes.
But first some words in general.
Although this topic is hardly ever broached, and most of the general public hears
nothing about it, the task of the riders is more than simply win races – their expertise
allows them to evaluate frame, suspension and engine designs, and give valuable
feedback to the engineers about the performance (or, as might be the case, the lack of
it) of their products. In some instances, this feedback and the influence thereof was
profound – it is well known, that great riders like Leslie Graham and Geoff Duke not
only influenced but vastly improved the road holding and handling of resp. the MV
and Gilera 500 cc four cylinders.
This was also the case with riders like Jim Redman and Luigi Taveri, who were very
good at road holding and frame evaluation resp. engines and carburation (Redman,
e.g., was an outstanding mechanic himself). They could analyse a problem and
exactly report back to the engineers what was wrong, and, based on their vast
experience, suggest changes for the better. Contrary to this, the great Mike Hailwood
was known to be an abject failure at this, and that might have been one of the reasons
nothing was ever done following his complaints about the big Honda – I wouldn't be
surprised if his only comment would have been: "It's bloody awful, mate!"
And now, on to the riders themselves.
On 5 May 1959, the Japanese riders arrived at London airport (see picture below;
photo Motor Cycle). From left to right: Giichi Suzuki, J. Suzuki, Naomi Taniguchi
and Teisuko Tanaka.
Picture below: Bill Hunt, the
team captain, the man who
fell off (photo Motor Cycle).
97
1960: The Japanese
works riders that year
were
Kunimitsu
Takahashi (picture far
left),
Sadao
Shimazaki,
Yukio
Sato (picture left) and
Naomi Taniguchi.
The other works riders were Australians
Tom Phillis (picture left) and Bob Brown
(picture right). Phillis acted as team
leader until his death in the 1962 TT of
Man during the 350 cc race. Bob Brown
was killed when he crashed on the
Solitude in Germany. When Phillis
crashed during practice for the Dutch TT,
Rhodesian Jim Redman joined the team,
at first on a race-to-race basis (see picture
below). After Phillis' death, he took over
as team captain until his retirement, aged
36, after his crash in the Belgian GP in 1966.
Redman was an absolutely brilliant rider, one of
the greatest ever, and a total professional, who
was, I feel, grossly underrated by most people.
He was an all-rounder, winning Grand Prix in
every solo class except the 50 cc, for which he
was simply too big. He won 46 GP for Honda
and is still the all-time most successful racer for
Honda, winning six world titles for them, two
times in the 250 class and four times in the 350
class. Jim was the first rider in the history of
racing to win 3 GP in one day with all new
race- and lap records, Assen 1964. Only one
other rider, Mike Hailwood, Brno (Czech.)
1966 and Assen 1967, ever equaled Jim’s
record – but not with all new record lap and
race times! Many people see him as the equal of
Phil Read, but in view of the much higher
power of the Yamahas, no doubt Redman was
the better man.
During the Belgian GP at Francorchamps, Jim Redman aquaplaned and crashed in
pouring rain, and broke his wrist. He returned for the Ulster GP, but the arm gave too
much trouble, so he didn't start. He again tried at the IoM TT, but the arm was still not
right, and it forced Redman to quit racing.
98
1961: and Luigi Taveri (see picture right), born in
1929 near Zürich, in Switzerland, joined the team.
He became a three times world champion 125 cc for
Honda. Although Taveri was mainly involved in the
50 and 125 cc classes, he would sometimes ride the
250 fours and the CR72 and CR77 production
racers, which earned him a third place in the 350 cc
world championship in 1963.
Thanks to some arm twisting by Mike
Hailwood's father Stan, Honda lent a 125
cc twin and 250 cc four to 21 year young
Brit Mike Hailwood (picture left with his
father Stan after winning the 125 cc class
on Man, 1961). Hailwood gave Soichiro
Honda his first TT victory in the 125 cc
class on Man. He went on to win his first
world championship that year, the 250 cc.
For some reason, Mike upset Mr.
Kawashima Kiyoshi, Honda's team
manager and later President, and it was
only in 1966 that he got a works contract,
after Honda was persuaded by Jim
Redman to do so.
Another man, racing Hondas in national races in England,
was John Hartle (picture right), a former MV works rider.
Although the works riders were not happy with these
"privateers", it gave Honda a lot of publicity, and that
was, and still is, what racing is all about.
During that year Japanese riders Moto Kitano and
Teisuke Tanaka competed in various races – the Honda
policy with regard to the Japanese riders seemed
sometimes unclear to
western observers, but
it was to nurture them
to later win world
championships.
1962: Bob McIntyre (picture left) joined the team,
after having had some Honda rides before.
McIntyre was the man who, for the very first time
in history, lapped the Isle of Man course at over
100 mph during the jubilee TT races in 1957 on a
99
Gilera four 500 cc. With the Honda 250 four he set a lap record on Man that year of
99.58 mph, but retired with oil problems. Later in the season he was tragically killed
when competing in a local race on a Norton. In my view, Bob McIntyre was the
greatest rider never to win a world championship.
Irishman Tommy Robb (picture left) also joined
the team. He came in third in the 350 cc world
championship and claimed a Honda 50 cc win that
year with the RC112 twin on Suzuka in Japan.
For some reason the team manager didn't like
him, and, after a poor 1963 season, he was sacked
in 1964 when he showed up late for practice for
the French GP.
A noteworthy "privateer" that year (1961) was
Derek Minter (right), the first man ever to lap the
Isle of Man course at over 100 mph on a single
cylinder (Senior TT 1960 on a Norton Manx), and
who got a 1961 Honda four on loan for the TT on
Man. Derek started the rumour that Honda were
not happy that he won the race, ahead of the
works riders. However, there were never any team
orders in the Isle of Man, says Jim Redman, as to
win there was too important for all riders.
Derek Minter chose to mainly stick to short
circuits in England, only occasionally venturing
onto the Continent, mainly Assen and Monza –
but on those occasions he was always very
successful!
1963: No changes to the team.
1964: Honda asked Jim Redman to find a new rider and he
chose a practically unknown rider, Irishman Ralph Bryans
(right), to join the team to concentrate on the 50 and 125 cc
classes. He won the world championship 50 cc for Honda a
year later.
Halfway through the season Tommy Robb and Kunimitsu
Takahashi (who later joined Nissan as a test driver) were
sacked.
1965: No changes to the team. During the last GP of the season, in Japan, Mike
Hailwood won the 250 cc class on a "privately" (because his contract with MV was
still valid) entered Honda six.
100
1966: Mike Hailwood (right) joined
the team as a works rider. In his book
"Hailwood", he complains: "Racing
has made me an old man before my
time." Well, the change with the 1961
picture is quite clear. However, he
couldn't complain about the pay:
Honda paid him £ 40,000 a year.
To assist Hailwood, after Jim
Redman's
retirement,
Redman
selected Stuart Graham, son of Leslie
Graham, the first ever 500 cc world
champion, to join the team.
1967: For some reason, Graham was
no longer part of the team, which
consisted of only Hailwood and
Bryans. At the end of the season,
Honda retired from Grand Prix racing.
101
A matter of handling.
Time and again the Honda GP racers have been described as atrocious handlers, to
such an extent, that all subsequent Hondas were doomed to live under the alleged
curse of bad handling and road holding. Where do all those stories come from? Well,
one powerful reason is, "because everybody says so". Even people who have never,
ever ridden a Honda know exactly how to tell the blood curdling tales about their road
holding.
A second reason is some silly statements by writers who should know better. E.g., in
his book "Honda GP racers", Colin MacKellar writes (page 48) that Honda only
started winning Grand Prix when they changed to English frames. This is blatant
nonsense. Honda, in what is called their "Golden Age", have never, ever used English
frames – the frames were pure Honda. They used some English parts, i.e. tyres (Avon
and Dunlop), rev. counters (Smiths, although also Honda counters were used), and
sometimes Girling rear shock absorbers. Two non-Honda frames were built for the
RC181.
One was designed by Colin
Lyster and built by the Italian
firm of Belletti, builders of the
Paton and Linto frames (see
picture left), which was not a
success, and one by Reynolds'
Ken Sprayson, which might have become
successful if it would have been further
developed. However, those frames did not have
Honda's blessing and were never used in GP
racing. Hailwood also experimented with Ceriani
forks and hydraulic disc brakes (see picture right;
photo Motor Cycle), but was not satisfied with
them and reverted to the standard Honda parts.
It should be noted, that at that time Ceriani forks
were considered to be the "standard" by which all
other forks were judged. They were used by MV,
Benelli, AerMacchi, Yamaha(!), Paton, Mondial
and Morini, to name a few. If Hailwood decided
that the original Honda forks were better, they
must have been very good indeed!
Actually, during the "Golden Age", the only person who complained about the road
holding and handling of the Hondas was the great Mike Hailwood – nobody, but
literally nobody else ever complained. Not Jim Redman, not Bob McIntyre, not Tom
Phillis, not Luigi Taveri – nobody.
In his book "Hailwood", written with Ted Macauley, Hailwood states (page 79): "The
old Hondas, the ones used in 1961, were bad handlers compared with other bikes. In
the light of their history of atrocious handling, Jim Redman comes out as a far better
rider than most people are prepared to give him credit for."
102
History of atrocious handling? Really? Then why did the same Hailwood write in his
previous book "The art of motorcycle racing", about the 1961 Hondas (page 166): "I
have already given my impression of the Honda 125 c.c. twin and there is little I can
add except to say it is, without doubt, the finest 125 I have ever ridden. Although it is
not nearly as outstanding in its class as the 250 c.c. Honda four, it is nevertheless a
superb machine which combines ample, smooth power with perfect handling." No
grounds for misinterpretation here, is there? And about the 250 four (page 169):
"This, like the 125, is a magnificent machine. When riding close to a Honda four its
handling looks frightful, but its looks belie it, for it feels perfectly all right and does
not seem at all skittish. I never fell off a 250 Honda in spite of some hair-raising
battles with riders of the calibre of Bob McIntyre, Tom Phillis, John Hartle,
Kunimitsu Takahashi and Jim Redman, so its handling must be all right." Very, very
clear, isn’t it?
All those Hondas had the same type of frame. All those Hondas I have seen being
raced by the aforementioned riders, and some I have ridden myself. Their handling
and road holding was beyond reproach. You don’t win that number of world
championships with machines that are really wanting in the handling department.
During one Dutch TT, in 1964, Redman won three classes, in furious battles with the
Yamahas of Read, all three with new race and lap records. On atrociously handling
machines? Come on!
And then again Hailwood changes his mind. "Hailwood" (page 76): "I really enjoyed
racing the 250, even though the Yamahas I raced against were quicker. The 250 was
quite well behaved and easy to handle. The 350 was okay, too." In his book "The
Story of Honda Motor Cycles", Peter Carrick wrote (page 77): "One of the greatest
racing machines of all time was Honda’s 297 cc six on which Hailwood won the 1967
350 cc world championship. It was Mike’s favourite machine, and……"
So, what does it all boil down to? No doubt the reputedly terrible handling of the big
RC181. To my knowledge, only two persons, other than Redman and Hailwood, have
ridden this bike: John Surtees and Allan Cathcart. Martin Hodder and John Cooper
rode the Reynolds framed version (picture below), and Hodder still found fault with
the bike (The Classic
Motorcycle, May 1996): "I
had proved for myself that
the
Reynolds
frame,
significantly better than the
Honda original in every
way, was not at all suspect,
and that the infamous
handling we had all
witnessed was down to a
combination of power,
undeveloped
suspension
and inadequate tyres."
The
conclusion,
or
statement: "…significantly better than the Honda original in every way…" is not his
to make: he had never ridden the originally framed RC181, and so couldn't compare.
But his conclusion about the suspension units and tyres is well noted.
Wrote John Surtees, who rode the original Honda framed RC181 (Classic Bike,
December 1985): "The rear units are down to their bump rubbers, which locks up
their suspension movement, and a reaction is then transferred to the front of the
103
machine." And, a little further on: "However, I would hesitate to blame frame flex or
whip without having the opportunity to modify features such as the rear suspension
pivot points, damping and spring rates, and wheel travel." Words like these, from an
out and out expert like John Surtees, are not to be taken lightly. John Cooper used the
word “bloody” a number of times in connection with the Reynolds framed bike,
without being specific, but Allan Cathcart, on the other hand, found the Honda a
handful, but didn’t complain much.
Moreover, how about the only other person than Mike Hailwood who has ever ridden
the RC181 in anger, Jim Redman? He won the first GP in Germany in 1966, looked at
a 22 seconds gap behind Agostini in the Dutch TT after Hailwood had crashed, but
fought back and won, and a week later, in Francorchamps, had trained 1 second faster
than Hailwood and 6 seconds faster than Agostini, but during the race he aquaplaned
and fell off in pouring rain – and that was it. He never complained about the big
Honda, on the contrary. With his permission I quote from his autobiography "Jim
Redman M.B.E. – Six Times World Champion", page 206:
Jim Redman on the Honda 500 four in the German Grand Prix
"Right from the start Mike had problems with the Honda’s handling. In some respects
the way the bikes handled was my fault, as years before I had elected to keep the
Hondas shorter and lighter than the MVs. This gave them more acceleration and top
speed and, as I knew I had Mike to beat, I figured this was the best way to do it. The
bikes jumped and wriggled a bit but, over the years, I had got used to it and I loved
the way they responded coming out of corners. In the early part of a race they
sometimes gave you a few good frights, but as the race progressed you got into the
groove and handled it. And the extra speed and acceleration meant you won races.
Mike came along, used to the way the heavier MVs handled, and was straight in at the
deep end. He did not like the jumping and wriggling one bit, which was especially
obvious with the 500. I thought then – and still do now – that the bike handles very
104
well; I’m much happier on the 500 Honda than on the 500 MV and feel sure I can go
faster on the Honda. I am amused that everyone who tests the 500 considers it an
unrideable monster just because Mike said it was. It just goes to show the respect
everyone has for him. I seem to be the only person in the world who thinks it’s a good
bike and handles well. Because it had received such bad press, when I got on it again
at Suzuka in 1996 I was a bit apprehensive, as I thought maybe I could not trust my
memory. Happily, once on board, I found it to be the same bike I remembered from
1966, which goes like mad for its age and handles very well. Of course, I could not do
it justice now, but I did at Assen in 1966 and you just can’t ride as I did that day on a
circuit like Assen if your bike does not handle well."
Here is the opinion of a man who’s a six-times world champion, who in my opinion
was one of the greatest riders of all time, and who won straight away the first two
races he entered with the 500 Honda.
I have always been convinced, that if Redman would not have fallen off in Belgium,
he would have been the 1966 500 cc world champion. If…
The caption with this picture, taken during the 500 cc TT of Man 1967, read
(translated from German): "And again the rear wheel of the Honda lifts off the
ground! Hailwood not only had to fight hard against Agostini over four laps, but also
against the frame of his Honda over the whole race!"
Anybody who knows anything about racing, can clearly see, that the lifted rear wheel
has nothing to do with the frame of the Honda: Either Hailwood is sitting up, braking
so hard that the fairing is nearly touching the front mudguard (meaning the front forks
are completely compressed), the left foot pushing down on the rear brake pedal, the
left hand grabbing the clutch while changing down – and that whole braking action is
exactly what makes the rear wheel lift (it would do so on any race bike, when the
front brake is powerful and applied hard enough) – or, on the other hand, it could well
be Hailwood landing after a jump – the end result is the same (many pictures of racing
bikes on Man show exactly the same as the picture of Mike above). But it was words
like these that strongly reinforced the bad reputation of the 500 cc Honda.
No doubt Hailwood had some hairy moments on the big Honda. However, it is wrong,
in my opinion, to blame it all on the Honda engineers and their frame creation – no
105
doubt the combination of inadequate rear suspension units (which had less than 60
mm travel, both the Showas and the Girlings), and tyre sizes that were hardly bigger
than are now used on 125s, played a major role in the handling problems of the
RC181. The world was simply not yet ready for the power of that bike, although, as
stated above, Jim Redman obviously had no problems…
Hailwood with the Reynolds framed Honda. The bike was entered under the name
HRS (standing for Hailwood Reynolds Special), so as to save Honda embarrassment
if the project would fail. During his first race on the bike, in Rimini in the spring of
1968, Mike fell off, but expressed his satisfaction with the overall handling of the
frame. The aluminium tank was made by Ernie Earles. Note that the engine is
equipped with the 1966 version of the reverse cone megaphones. For people who like
facts and figures: the frame was made from Reynolds 531 tubing, the main tubes
having a diameter of 44.5 mm with a wall thickness of 1.4 mm, the rest was made of
25.4 mm diameter tubing and the seat rails of 22 mm diameter tubes. It weighed 9.1
kg, the swinging arm, made from 38 mm tubing with a wall thickness of 2 mm, added
nearly 3 kg to this. Wheelbase 1397 mm. The frame was designed for 57 degrees of
lean, but that was still not enough for Hailwood…
106
The RSC Hondas
After the withdrawal of Honda from the Grand Prix racing scene in 1967, a group of
Honda engineers formed the Racing Service Club or RSC (later, the explanation for
RSC became Racing Service Centre or Racing Services Corporation). They developed
special racing parts for use by private riders, and sometimes even complete racing
motorcycles, often based on standard production models.
One of the first models developed during 1968 was the CYB350, also known as the
RSC350, a production racer based on the standard CB350 – although Honda
themselves called it the CB350R in their official documentation.
The engine had higher compression, a new camshaft, Kei-hin CR carburettors with 31
mm diameter, open
megaphones and a sixspeed gearbox. The
frame received some
extra tubes from the seat
rails to the steering head,
and a rev. counter,
special tank, clip-ons,
racing seat, rear set
footrests with aluminium
gear change and brake
pedals, aluminium rims
and a fairing completed
the bike. Honda claimed
over 50 PS for the
model, which seems
rather high with a view
to the 47 horses of the
CR77 production racer,
which was only 20 cc
smaller than the CYB350
107
(305 cc compared to the 325.6 cc of the CYB350), but had 4 valves per cylinder.
Later a model, which looked much more like a real production racer, with modified
front forks and magnesium brakes of 210 mm diameter, 4ls in front and 2ls in the rear
was sold (see pictures below).
Picture to the right shows
the lightened crankshaft,
compared to the standard
shaft.
108
After the success of the CR750 at the Daytona 200 miles race in 1970 (about which
later more), in September 1970, half a year after the Daytona win, Honda RSC
brought out a tuning kit for the CB750 street bikes, based on the successful Daytona
winner (see picture above).
Just as with the factory bikes, the bore was increased to 61.5 mm for a total capacity
of 748.6 cc. The compression ratio was 11 : 1, and the pistons had only one
compression and one oil scraper ring, which gave lots of problems – heat transfer
through the one compression ring was insufficient, so the pistons couldn’t get rid of
their heat and tended to seize. This was cured by increasing the clearance of the
pistons from 0.05 to 0.08 mm, but then compression loss occurred due to tilting of the
pistons. Some tuners reverted back to standard pistons, which cost a couple of horses,
but gave reliability and easier starting.
Valve timing was I.O. 20° btdc, I.C. 45° abdc, E.O. 45° bbdc, E.C. 20° atdc. Valve lift
was 9.0 mm inlet and 8.5 mm exhaust, with cold tappet clearance set at 0.15 mm.
Carburettors were 31 mm CR Kei-hins. Claimed power was approx. 90 PS at 9600
rpm at the crankshaft (see graph below), although many tuners mobilized more power.
Working on the porting alone was already good for more horses – the castings were
very rough, with marked steps in the inlet ports.
109
Not shown on the picture are the very expensive crankshaft, foot rests, the central
aluminium oil tank, the fairing and fairing stays, the mounting plate for the rev.
counter and oil pressure gauge and the gear change and brake pedals.
The front forks did not have the axle clamps with 4 bolts, but with the standard 2. It
was left to the lucky owner to modify the frame, buy the second disc and turn the
discs thinner to 5 mm to save weight (which was a terrible job because of the hardness
of the disc material!). Tyre sizes 3.00 – 18 front, 3.50 – 18 rear.
Honda offered the kit in three stages, and gave the following recommendations for the
various replacement parts.
1. Amateur (novice) model. Parts to be replaced:
Carburettors
Front brake
Rear brake
Seat complete
Clip-ons
Megaphones set
Foot rests set
Front forks
Rear shock absorbers
2. Junior model. Parts to be replaced in addition to the ones mentioned above:
Camshaft
Valves
Valve springs
Crankshaft
A.C. Generator
Ignition cam
Cam- and primary chains
3. Senior model. Parts to be replaced in addition to the ones mentioned above:
Cylinder head
Cylinder
Transmission (gear box)
Oil tank and -cooler set
Pistons
Piston rings
Very few people bought the complete kit – for the price of the complete kit you could
buy four brand new CB750 Hondas…
Power curve as published by Honda.
Contrary to the work’s GP racers, this is
the crankshaft power.
110
The pictures above (photos J. Kortekaas) show my own CR750, which was raced in
Australia. Some parts were not stamped CR750, but CB750R. I found the bike in
deplorable state within 10 minutes' driving from my then home in Western Australia –
the discovery of old racing motorcycles is often a serendipitous affair!
111
A prominent development engineer, test rider and
racer in the RSC was Morio Sumiya, (picture left)
who worked on the CR750 in Japan. See picture
left and below. As can be seen, for some reason
(exhaust noise limitations?) the bike sported a 4
into 1 exhaust system, and had a different
generator cover – probably now housing an
electronic CDI system.
112
Development of the CB500-four
During the Tokyo show of 1972, a CB500-four based production racer was introduced
by the RSC, with a cylinder capacity of 650 cc. See picture below. No data as regards
bore and stroke, or power and engine speed were given.
The bike had a double disc brake at the front, and still the usual drum brake at the
rear, and four separate exhaust megaphones. There was a dry-sump lubrication system
with central oil tank as compared to the wet-sump system of the standard CB500. Oil
pumps just behind the generator cover. The fairing shows the openings for the small
oil coolers as previously used on the work's Grand Prix racers and the CR450.
The position of the spark plug shows that there couldn't be 4 valves per cylinder, but it
should be possible that two inlet and one exhaust valve were used as in later
developments. Fact is, that the original CB500 head was totally unsuitable for racing.
The large generator cover had been replaced with a much smaller one and contained
probably an electronic system.
113
To create a lighter and more competitive racer for the 750 class, during 1975 this 650
cc version was further developed into a 750 cc race bike, still based on the CB500
street bike, which, although being 750 cc, was still called the CB500R. (Photos Honda
Collection Hall)
Bore and stroke were changed to 66 x 54.76 mm, giving a total capacity of 749.38 cc.
The engine retained its single overhead camshaft, but got 3 valves per cylinder – 2
inlet valves and one exhaust valve, a system also used on some street Hondas.
Camshaft drive was by gear train i.s.o. the chain of the standard CB500. Ignition was
by electronic (CDI) system. Power output was given as 86.7 PS at 11,000 rpm.
Lubrication was, again, contrary to the standard bike, by dry sump system, with a
114
central oil tank. The two small oil coolers in the sides of the fairing had been replaced
with one cooler underneath the steering head. The clutch ran dry and the gear box
contained 5 speeds.
The four separate exhaust pipes and megaphones had been replaced with a four-intoone system, and the rear drum brake was replaced with a disc brake, while the spoked
wheels had been replaced with cast ones. Unfortunately this development stopped
when Sumiya was killed in a race accident during the 24 hours endurance race at the
Bol d’Or 1975.
RSC also developed two-stroke models, but they are outside the scope of this book
and will not be discussed.
115
Hondas at Daytona
In 1965, Honda introduced their first "big" street motorcycle, the 450 cc twin,
nicknamed the "Black Bomber", which set new standards for street bikes – two
overhead camshafts, torsion bar valve springs, constant vacuum carburettors and some
45 PS at 9,800 rpm, which meant 100 PS per liter, power hitherto only reached by
pure racing machines.
Bob Hansen, the National Service Manager for Honda in the United States, who had
his personal racing team, using orange-and-white painted Matchless G50s (a tate of
affairs which Honda ignored), persuaded Honda in 1967 to prepare a couple of CB450
based racers. They were entered under the Hansen team banner in the same orangeand-white colours.
In the amateur race, Jim Odom was fighting for the lead with Walt Fulton Jr. on a
Harley Davidson, but lack of ground clearance because of the low-slung megaphones
brought him down in the hairpin.
In the subsequent main 200 miles race, Swede Savage finished a creditable tenth,
handicapped as he was by a broken rev. counter cable and a non-functioning rear
brake for half the race.
Changes to the C450 engine were relatively small. Bore and stroke remained 70 x
57.8 mm, giving a total capacity of 444.9 cc. Drive to the dohc was still by chain. The
compression ratio was raised from 8.5 : 1 to 9.2 : 1, and the camshafts were modified.
Unconfirmed rumours have it, that the camshafts had the same timing and lift as the
ones which were later used in the CB450 K1, the five-speed version introduced in
1968 (which initially sported indeed a couple of horses more than the four-speed
version).
The crankshaft was lightened by turning down the sides to a conical shape, and the
conrods were polished, see picture below for comparison to the original crankshaft.
116
The 32 mm vacuum carburettors were replaced with Kei-hin CRs with 35 mm
diameter. Ignition was by crankshaft mounted, low-tension generator and HT coils
with the contact breakers in their normal position on the left-hand side of the exhaust
camshaft – ignition timing was retarded 5 degrees to 40 degr. btdc. To facilitate
timing, the generator cover was transparent. The clutch operating mechanism was
replaced with a works GP racer type (which doesn’t use the
worm type clutch operator but a bell-crank type, see picture
right), and two small oil coolers were installed as on the GP
racers, to maintain an oil temperature of 100-110 degr. C.
A new clutch cover replaced the original one, and the
rotating oil filter was removed. The oil pump was still the
plunger type. No power output figure was given, but, based
on my own experiences with tuned CB450 engines, would
guestimate it at some 54 to 56 PS. Red line on the
tachometer was at 11,000 rpm. Electric starter motor and
kick-starter were of course removed. The engine got the
same breather dome as the works- and production racers.
The sectional drawing below shows the standard engine on
which the CR450 was based – a couple of years earlier,
everybody would have thought this was an out-and-out
racing engine. Clearly visible are the overhead camshafts,
the rockers and the torsion bar valve springs (by the way, normal helical valve springs
are nothing but torsion bars that are coiled – the way they work is exactly the same).
Size of the inlet valves 37, of the exhaust valves 31 mm. Primary drive by gears.
Nothing was said about the gearbox, but no doubt this got a more close-ratio cluster.
117
The frame lost its vertical tube behind the engine, and got two new tubes, running
from the swing arm bearings up to the seat rails, with a cross bracing above the swing
arm bearings. All tubing connections got extensive bracing by steel sheet gussets.
Front forks came from a CL model, with the hydraulic damping modified to suit road
racing. Brakes came from the CR production racers, 200 mm four leading shoes at the
front, and 180 mm two leading shoes at the rear. Dry weight was 141 kg.
118
The modifications to the
standard bikes were extensive.
The bore was enlarged from 61
to 61.5 mm, with the stroke
remaining at 63 mm, giving a
swept volume of 748.6 cc
against 736.5 cc standard.
Compression ratio was raised to
11 : 1. The inlet valves were
enlarged from 32 to 33.5 mm; in
order to obtain the room for this
the exhaust valves were made 1
mm smaller: 27 i.s.o. the
original 28 mm. A "hotter"
camshaft with more lift was
employed, and the standard 28
mm carburettors were replaced
with 35 mm racing Kei-hins
(This made the area of the
carburettors 9 % bigger than that of the inlet valves). Four separate megaphones
replaced the standard system. Ignition was by low-tension racing magneto on the left
hand side of the crankshaft with external HT coils and contact breakers on the right
hand side of the crankshaft; ignition timing was fixed at 35 degrees btdc.
The crankshaft was lightened and polished, as were the conrods.
The gearbox got a close-ratio cluster, the electric starter motor and kick-starter were
removed. The engine still had the dry sump lubrication, now with a central,
aluminium oil tank containing 4 litres of oil, and an oil cooler under the steering head,
with an oil pressure gauge.
Claimed output was 96 PS at 9600 rpm at the crankshaft.
120
The standard frame was used, but all un-necessary parts and lugs were removed. Front
fork and rear shock absorbers were special, with the front fork legs having four bolts
to clamp the axle instead of two. The front brake got a second disc added and was
laced in an 18" aluminium rim against the 19" steel standard one. The discs were
standard, but were turned thinner from 7 to 5 mm to save weight. At the rear a
massive, electron 205 mm two leading shoe brake replaced the 180 mm standard
brake. Fuel tank was aluminium and held 26 litres, the seat was polyester. An
hydraulic steering damper was added, the footrests position was changed, and gear
change and rear brake pedals replaced with aluminium ones. Weight was reduced to
163 kg through the extensive use of titanium and magnesium.
Honda's own reaction to the Daytona victory was remarkable, to say the least. Where
other manufacturers would have shouted to the world that they had won one of the
most prestigious road races in the world, Honda kept silent. Not a word of the victory
appeared in advertisements; it was as though the public relations people were
embarrassed by it. And the Honda Collection Hall doesn't contain a CR750…
After Daytona, the CR750 Honda made one more (unsuccessful) appearance under
Sumiya, this time in Europe during the ”Race of the year” at Mallory Park end 1970,
after which it returned to Japan once more, never to be seen outside that country
again.
Morio Sumiya during the race of the year at Mallory Park
121
HONDA'S ENDURANCE RACING 1976 – 1981
Introduction
The history of Honda's works participation in the Coupe d'Endurance races during the
years 1976 through 1981 has not the same appeal and glamour as the history of their
"Golden Age" of Grand Prix racing during the sixties. There are a number of reasons
for that.
In the first place, the number of events per year, six, later, when the series got world
champion status, in 1980, some more, compared to the eleven to twelve events in the
case of the GPs, and the fact that the Grand Prix series were about world titles – the
Coupe d'Endurance was a European affair until 1980.
Then there were the bikes. During the sixties, the racing scene was dominated by the
three Japanese firms Honda, Suzuki and Yamaha, with MV struggling in the 350 and
still winning in the 500 cc class, and a number of other factories still in the fight –
Jawa, MZ, Benelli, AerMacchi, Norton, AJS and Matchless to name the most
important ones. Razor sharp competition saw the emergence of screaming single,
twin, three, four and even six cylinder engines, with ever rising engine speeds, which
made it a time highly interesting not only to the spectators but also to the technically
interested. Compared to those exotic machines, the endurance racing dominating
Honda RCB and RS racers, derived from the touring CB750 and later from the CB900
Bol d'Or type, were rather straightforward and not half as exciting as their GP
predecessors.
And, lastly, there was indeed their dominance. Participation in the Coupe d'Endurance
was open to "improved" production motorcycles. However, the requirements were so
vague, that the way was open to compete with practically completely new designs,
and that possibility was rigorously exploited by Honda. Most teams in those days
were "private", and to compete against the might of Honda was a daunting task. The
result was that the series were totally dominated by the Honda RCBs, which in the
end makes for less interesting racing. The only really interesting year proved to be
1980, but then Honda was plagued by stupid bad luck, especially with riders that fell
off.
However, it was still an interesting period, and most definitely an integral part of
Honda's race history, so let’s have a closer look at it.
Zandvoort, The Netherlands, April 1976.
Excitement in the pits in the Dutch circuit in the dunes bordering the North Sea – for
the first time in 9 years a real Honda factory team had arrived for the 6 hours
endurance race.
Honda had retired from GP racing in 1967, and although they had made a brief
appearance for the Daytona 1970 200 miles race with the race-tuned CR750, that had
not been a real "works" effort, and after winning that race the machines went back to
Japan and were hardly seen again. Then, late 1975, Honda announced that they would
be returning to the circuits in 1976, but this time in endurance racing. As it so
happened the Dutch 600 km race was the first endurance race that year, and it was
there that the Hondas made their first appearance of the season. The effort was run
and coordinated by Honda France under management of Jean-Louis Guillou.
However, in Zandvoort the team showed up with two machines, riders Leon and
Bowler, entered by Honda France, and Stanley Woods and Charlie Williams, entered
122
by Honda UK, an English and a French pit crew and a large number of Japanese
technicians and – a total of 31 people! Hardly any details of the machines were
known, and the fact that the mechanics only spoke Japanese and a couple of words
French didn't really help things.
The race was won by Christian Leon and Roger Bowler, who were much faster than
the team Woods/Williams. The latter team also had ignition problems during the race,
and, after falling back to 24th position, they retired. This race, however, was a nonchampionship event.
Christian Leon on the RCB (photo Don Morley)
The 1976 FIM Coupe d'Endurance started with the 1000 km of Mugello, followed by
the 24 hours of Barcelona, the 24 hours of Liege in Belgium on the old
Francorchamps circuit, the Bol d'Or in Le Mans and the season's closure at the 400
miles of Thruxton.
The supremacy of the Honda RCB
racers was so great that all the races
were won by them. Christian
Leon/Jean-Claude Chemarin won in
Mugello, Barcelona was won by
Woods/Williams
with
Leon/
Chemarin second, but Leon/
Chemarin won Liege.
During training for the Bol d'Or
Leon fell off and broke a collarbone,
after which Alex George took his
place. It made no difference – they
won. This win gave Chemarin the
European championship title. For
Thruxton he teamed with Pat Evans,
and came in second behind Christian
Huguet and Roger Ruiz on another
Honda RCB.
Chemarin, first champion (photo Terry Howe)
123
The machines
The engine of the Honda RCB1000 (photo Honda Collection Hall) as it was known
was based on the CB750 four, but with numerous modifications. A bore and stroke of
68 x 64.8 mm gave a total capacity of
941.3 cc (initially a capacity of 915 cc
was mentioned). Compression ratio was
11 : 1, claimed power output 115 PS at
9,500 rpm, although at least one bike was
measured at 118 PS, with a torque of 10.2
kgm at 8,500 rpm.
The original cylinder head with one ohc
had been replaced with one with cast-in
cast-iron combustion chambers and with
two overhead camshafts, which ran in
plain bearings, and 4 valves per cylinder.
Valve sizes: inlet 28 mm, exhaust 24
mm. Valve clearance was set with
shims. The camshafts were coupled
with gears, but the combination was
driven by a duplex chain (see picture
above; photo J. Gassebner). The
camshafts, which were split in the
middle, ran in plain bearings without
separate bearing shells.
The horrible original primary drive
with two separate chains of the CB750
had been replaced with gears (see picture above, photo J. Gassebner), which also
drove the electronic CD magneto ignition, which sat on top of the crankcase,
underneath the carburettors. This system fired every revolution, so one spark was
124
effective, and one spark was idle, firing in the exhaust stroke. As can also be seen in
this picture, the big end- and main bearings were plain bearings, and the driven gear
on the primary gearbox shaft contained a shock absorber. Diameter of the big-end
bearings 36 mm, gudgeon pins, which were taper bored, 17 mm. The crankshaft was
made of two halves, welded together. It had the now well known configuration with
bob weights for balancing, but no flywheels, other than the rotor of the AC generator,
which was situated on the left hand side end of the crankshaft. It was of a much
smaller size than the original, and had an output of 150 W. For pure daylight racing,
the generator was removed, so giving more ground clearance.
The pistons had two compression rings and one oil scraper ring.
Carburation was by 4 Kei-hin
carburettors of the constant
vacuum type with 34 mm
diameter (some sources say 32
mm), cast in magnesium and
provided with long bell mouths
and transparent (Perspex) float
bowls (see picture left).
The exhaust system consisted of a
4-into-1 system that initially gave
some problems because it
exceeded the allowable noise
level. The gearbox was a fivespeeder. On the back of the engine
was the traditional breather dome,
well known from the old GP and
production racers. The crankcases were painted black (as were the cylinder block and
head) and were cast in aluminium. The engine-, camshafts- and sump covers were cast
in aluminium-magnesium alloy. There was no electric starter, the bike was kickstarted.
125
The dry-sump lubrication system contained 7 l oil, with an oil cooler under the
steering head. Relief valve set pressure of the SAE 40 oil was 5,5 kg/cm2, and the
temperature had to remain below 110 °C.
Picture above shows the clutch and gearbox. The narrow kick-starter gear wheel also
drives the trochoid oil pump.
The engine was housed in a well built, but traditional tubular frame, with telescopic
forks with 120 mm travel, and two conventional, but especially for this bike
developed De Carbon gas-filled rear shock absorbers with 150 mm(!) travel. The
initially used French cast magnesium SMAC wheels were soon replaced with Honda's
own "Comstar" wheels. Those wheels were built up from two-sided pressed stainless
steel "spokes", riveted to spun aluminium rims. Brakes were double discs in front and
a single disc at the rear. Tyre sizes 3.25/400 - 18 front, 3.50/5.75 - 18 rear.
Total weight of the bikes was 187 kg, of which 87 kg was on account of the engine
alone.
Some sources say ten of these bikes were built, others say four. Fact is, that after the
1976 season, one bike went to Germany, one to Holland, one to Belgium and one to
the Swiss Honda importer, while other teams showed up later using RCBs.
The pictures below show the "naked" bike.
126
This superb drawing by Laurence Watts shows the innards of the RCB engine in
many details. Behind the cylinder block the ignition magneto. Three plain bearings
per camshaft half.
127
1977
Overview
The success story of 1976 was repeated, but to an even greater extent, in 1977. There
were 6 championship races for the Coupe d'Endurance, and a number of nonchampionship events, of which Zandvoort was again the season opener. In atrocious
weather, with rain and hailstones, Leon/Chemarin won the race on the new 1977
RCB, followed by Marc Stinglhammer/Jack Buytaerts (Belgium), Harry van den
Hout/Leo Spierings (Netherlands), and Christian Huguet/Jacques Luc (France), all on
Honda RCBs.
To give an example of the pit work: changing a rear wheel took 30 seconds, changing
the front wheel a mere 15!
The championship opener was in Misano, were Leon and Chemarin led the race until,
in the 120th lap, Chemarin fell off because of oil on the rear tyre. Subsequently the
race was won by Green/Maingret (GB), followed by Stan Woods/Charlie Williams
(GB), both on Honda RCB.
The oil system was definitely a weak point of the RCBs, and gave (leakage) problems
on several occasions.
The 8 hours race on the Nürburgring was won by Woods/Williams, this time Leon fell
off.
(picture
right:
Woods).
Next was the 24 hours
of Barcelona, won by
Christian Huguet/Pentti
Korhonen, 2nd place
was for Leon/Chemarin,
3rd J. Luc/Benjamin
Grau, 5th Stinglhammer/
Buytaert, 6th Tuxworth/
White, all on RCBs.
The non-championship
race at Paul Ricard was
won by Leon/Chemarin, followed by Luc/Vial.
The 24 hours of Liege was for Jacques Luc/Pierre Soulas, with Leon Chemarin 2nd,
Schneider/Dyrda 3rd, Mooster/Burki 4th, and Woods/Williams 6th, all on RCBs.
The Bol d'Or, considered to be the most prestigious and important race of the
endurance calendar, was won by Leon/Chemarin, with Korhonen/Huguet 3rd, Helmut
Dähne/Egid Schwemmer 4th, Bardi/Ferreira 5th, Buytaert/Stinglhammer 6th and
Spierings/Van den Hout 7th. Last race of the season was the 500 miles of Thruxton,
won by Woods/Williams, followed by Huguet/Korhonen, Leon/Chemarin,
Rutter/Marshall and Luc/Soulas, again all on RCBs. Again all championship races
were won by Honda RCBs.
The European championship was won by Leon/Chemarin, followed by
Woods/Williams, Huguet/Korhonen, Green/Maingret, Soulas and Luc – an excellent
result for the Honda RCBs.
128
The bikes
For 1977 the bore was increased to 70 mm, bringing the total capacity to 997.5 cc.
Carburettor diameter 35 mm. Claimed power rose to 125 PS at 9,000 rpm (a
conservative claim, one bike at least was measured and pushed out 127 PS at 9,000
rpm), and the top speed was over 270 km/h. The AC generator disappeared from the
crankshaft and was placed on top of the crankcase, together with the ignition magneto.
129
Many teams riding the '76 RCBs updated their machines
in accordance with the '77 specifications. It appeared that
a set of 35 mm Kei-hin carburettors cost some US$
6,800….yes, six thousand eight hundred! And we're
talking 1977!
The exhaust system was changed from 4-into-1 to 4-into2-into-1. There was also a new, lighter frame, constructed
in Reynolds 531 tubing, and through the extensive use of
titanium and electron the total dry weight was reduced to
just under 170 kg. The oil cooler moved into the nose of
the fairing (picture left by Terry Howe).
Some teams, using the '76 RCBs, used frames built by Dutch frame specialist Nico
Bakker (see picture below), some with excellent results, although at least one team,
notably the Dutch, preferred the original Honda frame.
Guus van de Beek with the Bakker framed RCB at Zolder (Photo "Motor", The Hague)
130
1978
Overview
As had happened before, Honda reduced their works effort for the 1978 endurance
season, and there was only one real works RCB for Leon and Chemarin, and one
semi-works bike for Woods and Williams. Notwithstanding that, the Honda
dominance was again total.
Season opener was the non-championship 24 hours of Le Mans, which was won by
Leon/Chemarin on the '77 RCB. The next race was the non-championship 600 km of
Zandvoort, won by Woods/Williams on the new 1978 RCB, while Leon/Chemarin
were plagued by clutch problems and finished fifth.
Next was Liege, the first race counting for the European championship, which was,
apart from the winners Jack Buytaert/Jacques Luc on a "private" Honda RCB, a total
Kawasaki event – they were placed second, third, fourth and fifth. Leon/Chemarin's
had to give up, leading the race, with unspecified engine problems.
The 1000 km of Misano, on the "Autodromo Santamonica", was won by
Leon/Chemarin, followed by Green/Williams, also RCB mounted, and the 8 hours of
the Nürburgring was again for Leon/Chemarin followed by Green/Williams and
Dähne/Schwemmer on RCBs.
Leon and Williams at the Nürburgring
Since the new 1978 RCB had been giving problems in Zandvoort, the following three
races in Liege, Misano and the Nürburgring had been contested with the '77 model,
but for the 24 hours race of Barcelona the 1978 RCB was used. While leading the
race, Chemarin was hit by Palomo, who piloted a Ducati with Grau, and both riders
fell off. Both machines were lightly damaged, but it took the Honda crew only ten
minutes to get the bike going again, minus its fairing. Because of the delay,
Leon/Chemarin were now in fifth position, but six hours later they were back leading
the race, which they won with a new record number of laps. Second were
Williams/Woods, third Luc/Buytaert, all RCB mounted.
The Bol d'Or brought a surprise, in that from lap two the race was led by Patrick Pons
and Christian Sarron on an OW31 Yamaha, with which they kept a constant lead of
three laps over Leon/Chemarin. After some 17 hours, Pons suddenly increased the
131
lead to six laps, but that proved too much for the Yamaha, resulting in a broken
crankshaft. The race was then duly won by
Leon/Chemarin, with Luc/Rigal second and
Woods/Williams third, both teams on RCBs. Of
the first ten teams, eight were Honda mounted.
Last race of the season was the 1000 km of Brands
Hatch, which was won by Woods/Williams, with
Leon/Chemarin second and Green/Murray fifth on
RCBs.
The European championship was again won by
Christian Leon and Jean-Claude Chemarin, third
was Charlie Williams Honda RCB), fourth Jacques
Luc (Honda RCB), fifth Gary Green (Honda RCB)
and sixth Roger Ruiz (National Moto) and Stan
Woods (Honda RCB).
Leon and Chemarin, champions again.
All races during 1978 were won by Honda RCBs, except two non-championship
events: Mettet by Cowie/Toleman on a Kawasaki and Suzuka by Cooley/Baldwin on
Suzuki.
Sometimes the lower half of the fairing was removed to keep the riders cool
The bikes
In 1978 the power output rose to 130 PS. Ignition and AC generator moved to the
ends of the crankshaft again, and the oil cooler was moved back to its place under the
steering head. The clutch was now running dry, outside the crankcase.
132
Because of heavy mist, the 24 hours of Liege became 20.5 hours, and was won by
Fontan/Moineau on the RS.
Fontan at Liege.
Misano was won by Huguet/Hubin (Kawasaki), with Fontan/Moineau second.
The battle for the world title ended with Fontan/Moineau world champions on Honda
RS, with Huguet second and Dähne third. Chemarin finished sixth, Leon ninth.
The Bol d'Or, not counting towards the world title, was won by Gross/Samin
(Suzuki), followed by Monin/Green (Suzuki) and Huguet/Hubin (Kawasaki).
The bikes
137
As already mentioned, the 1980 RS racers were no longer based on the CB750 engine,
but on the CB900F "Bol d'Or". The 1980 FIM rules and regulations stipulated a.o. that
cylinder head and crankcase castings should be equal to the ones used in the
production machines, and the RCB engines based on the CB750 simply didn't comply.
Bore and stroke were 70 x 69 mm for a total capacity of 1062 cc. Compression ratio
10.5 : 1. Claimed power output was still 135 PS at 10,000 rpm. Inlet valve diameter
26 mm, exhaust valve diameter 22.5 mm. Carburettors Kei-hin VB 51 A – 32 mm CV
(according the FIM rules, standard carburettors had to be used). The ignition and AC
generator were situated on the crankshaft ends, as in the production models, and the
engines used the Morse chain camshaft drive and primary drive (albeit with a wider
chain) of the production models.
Contrary to the standard CB900F, the RS1000
had dry-sump lubrication with a double
trochoid oil pump on the left side of the
gearbox.
The frames were similar to the ones used in
1979.
Various private teams used the "B.R.S.C."
(British Racing Service Centre) versions
(picture right), which had a bore and stroke of
67.8 x 69 mm for a total capacity of 996 cc.
Claimed power output was 125 PS at 9,500
rpm, torque 10.7 kgm at 7,000 rpm. Inlet
valve diameter 26 mm, lift 8.62 mm, exhaust
valve diameter 22.5 mm, lift 8.14 mm.
Opening angle of both valves was 255 degrees
at 1 mm lift. Carburettor diameter 32 mm.
Camshaft drive and primary drive by Morse
chain.
At first it was rumored, that at the end of 1980, after five years' running, Honda would
withdraw from the endurance racing scene. Their supremacy of the earlier years had
for a great deal disappeared, due to the new FIM rules (as usual hampering
development), which gave other teams a chance to catch up, since Honda was no
longer allowed to use their technical expertise to the
full. Since they had won the European championship 4
years running, and won the first world championship in
1980 – they had achieved everything they had set out to
do.
However, Honda nevertheless entered the 1981 season,
albeit with a much reduced effort. There were two
teams, with American riders Mike Baldwin and Dave
Aldana, and French riders Jean-Claude Jaubert and
Dominique Sarron, brother of Grand Prix racer Christian
Sarron. The teams were entered by Honda France and
were again managed by Jean-Louis Guillou (right).
138
1981
Overview
First race of the season was the 24 hours of Le Mans.
After a pit stop to tank, Baldwin noticed an oil leak, and rode back through the pit
lane to his pits. However, driving back contravened the regulations, only pushing the
bike back was allowed, and Baldwin was disqualified. That left Jaubert and Sarron on
the second Honda, with which, from the 13th race hour, they held second place behind
the very fast Performance Kawasaki of Kawasaki-France. Then, at half past ten on
Easter Sunday, after 21 race hours, Jaubert fell, and for Honda the race was over.
The race was won by Huguet and Chemarin, former four times European champion
on the RCB Hondas, on a Kawasaki. They were followed by Guirden/Auguin (Fr),
Oudin/Coudray (Fr), and V.d. Wal/Buytaert (Nl/Be), all on privately entered Hondas.
Next race was the eight hours of the Nürburgring. Again two teams started for Honda,
Baldwin/Aldana and Jaubert/Sarron. Neither of the 4 Honda racers had ever before
ridden on the notoriously difficult circuit of 22.8 km length with its 40 right- hand and 33 left-hand corners. Nevertheless, Baldwin managed to appear from the first lap
with an advantage of 500 m. However, some hours later, while they were lying in 6th
position (Baldwin was suffering from a previous practice fall) they had to retire with a
defective rear brake. The race was subsequently won by Jaubert and Sarron on the
second Honda, followed by Huguet/Chemarin (Kawasaki), Pierre-Etienne
Samin/Jacques Luc (Fr) (Suzuki) and Raymond Roche/Jean Lafond (Fr) (Kawasaki).
In Francorchamps, Baldwin and Aldana had to retire, while Jaubert and Sarron only
managed a fourth place. Winners were Samin/Luc (Suzuki), followed by
Roche/Lafond (Kawasaki), Chemarin/Huguet (Kawasaki) and Sarron/Jaubert
(Honda).
At the Bol d'Or in France, which didn't count for the world championship, Sarron and
Jaubert won, followed by Berthod/Monnin (Fr) (Kawasaki), Tost/Ruiz (Ge/Fr)
(Honda) and Huguet/Chemarin (Fr) (Kawasaki) Baldwin and Aldana only managed
5th place. In general the performances of the American duo were not what had been
expected of them, and initially Guillou had not been in favour of their employment,
but he was overruled by Honda, who thought that Baldwin and Aldana were at that
moment the best four-stroke racers in the world.
The last race of the season was the Suzuka 8 hours race, and here Baldwin and Aldana
won, with second Samin/Luc (Suzuki), third Roche/Lafond (Kawasaki) and fourth
Chemarin/Huguet (Kawasaki).
The world championship was won by Jean Lafond and Raymond Roche (Kawasaki).
The Bikes.
The RS1000 used during 1981 were practically the same as the ones used during the
previous year. Power was given by Honda as "over 130 PS" at 9,500 rpm, although
some sources mentioned 150 PS. Bore and stroke were 67.9 x 69.0 mm for a total
capacity of 999.36 cc. Maximum torque was 10.0 kgm at 7,500 rpm. Carburettors
were of the Constant Vacuum type with a diameter of 35.5 mm, and the ignition
139
system was a fully transistorised one. Contrary to the previous bikes, they now had
wet-sump lubrication. Clutch was dry, driving a five-speed gearbox. Weight was
given as 165 kg, tyre sizes 3.25/4.50-18 front, 3.75/6.50-18 rear (photos Honda
Collection Hall).
Pictures show the bike as ridden to
victory by Mike Baldwin and Dave
Aldana during the 8 hours of
Suzuka.
140
The NR500 Story
In 1977 Honda announced that they would be returning to the field of Grand Prix
racing with a 500 cc motorcycle. This announcement, without any indication of the
type of engine, two-stroke or four-stroke, number of cylinders etc., gave rise to a
flurry of speculations in articles in the motorcycle press of the day. It was quite clear,
that everybody agreed it would be a four-stroke – it was inconceivable that Honda, the
great champion of four-stroke technology, would revert to two-stroke technique. But
there the consensus ended.
The well known motorcycle journalist and racing motorcycle expert Vic Willoughby
gave as his opinion ("Motorcycle", week ending 22 April 1978) that Honda would go
for a four-cylinder abreast, with water cooling, 4 valves per cylinder and 6 speeds – in
other words, apart from the water cooling an updated RC181 engine. The Japanese
magazine "Moto Rider" also opted for a very narrow four. This is not as impractical as
it seems – the 1967 RC181 was an underdeveloped engine, with a mean piston speed
of only 19.2 m/s at 12,000 rpm. If Honda could have maintained the Pme at a higher
engine speed, say, 14,250 rpm, giving 22.8 m/s mean piston speed, the power would
have risen to 125 PS, and there's no reason they couldn't have changed the bore/stroke
ratio and have an even larger piston area. Then, in February 1979, an article appeared
in Motorcycle Weekly, stating that Honda would go for a V-four with rotary valves,
either a conical Aspin type valve or a cylindrical valve, made of a ceramic material to
combat heat distortion. It was then that I wrote an article in the Dutch magazine
"Motor" (No. 8, February 1979, page 434), stating that Honda would build a semi Veight, by using the double-piston principle. That construction was well known from,
a.o., ships' engines and the Puch, Garelli and TWN two-stroke motorcycles. It boils
down to the use of one cylinder with two pistons working against each other, and then
folding the cylinder into a "U" form to have the pistons side by side. Cover the two
pistons with a common combustion chamber and voilà! For the FIM it would still rate
as a four cylinder, but the actual working would be like an eight cylinder. I predicted
18,500 rpm and a bore and stroke of 48 x 35.7 mm for 130 PS.
141
And that was exactly what Honda did. When they unveiled their new weapon, the 0X
(see picture above, photo Honda Collection Hall) it was a double piston semi V-eight,
with an included angle of the cylinder banks of 100 degrees, the only difference with
"my" design being the use of one oval piston i.s.o. two cylindrical pistons next to each
other, but their figures were uncannily close to mine: an aim of 130 PS (although
initially only approx. 100 PS was achieved) at 19,000 rpm and a stroke of 36 mm! For
the oval bores (they are actually not oval, an oval – meaning "egg-shaped" – having
no straight lines, but for simplicity's sake we‘ll stick to oval) they gave the dimensions
of 93.4 x 41 mm for a total capacity of 499.5 cc. The longish pistons needed two
conrods to guide them in a stable manner (just like two separate pistons would have
needed), and there were 8 valves and two 8 mm spark plugs per cylinder.
Compression ratio was 10.5 : 1. Valve sizes were 18 mm for the inlet valves and 16
mm for the exhaust ones, with shaft diameters of 3.8 mm. Included angle of the valves
was 65 degrees. There were 4 double choke carburettors of 22 mm diameter and 8
exhaust pipes – to all intents and purposes an eight cylinder with 4 bores. Ignition was
with a fully transistorised system. Lubrication system was wet sump. The cylinders
were made of aluminium with chromium plated bores. The crankcases were cast in
magnesium. The drive to the camshafts was with a gear train, located at the right-hand
side of the engine. On the same side was the dry clutch, which was driven via a
jackshaft which took its drive from a central gear on the crankshaft. At the end of the
1979 season, the engines produced 108 PS with the flat-slide carburettor size
increased to 26 mm. In the end Honda claimed for this engine 115 PS at 19,000 rpm
with a torque value of 4.6 kgm at 16,000 rpm.
142
Was the engine revolutionary (see picture above), so were the cycle parts. The frame
was an aluminium monocoque construction, in two parts. The front part comprised the
fairing as an integral part of the frame; in the sides of the fairing the radiators for the
engine cooling were incorporated.
The front forks were of an
upside-down version, with
the springs in front of the
fork legs – and in front of
them were the brake
calipers – and all that was
in front of the wheel
spindle! If ever there was a
construction to induce
sluggish steering it was
this one. See picture left.
The fairing didn't sport a
conventional
curved
screen (there was hardly
anything conventional about this bike) but a very small upright screen.
Wheels were Comstar, and for the first time since the Jawa racers of the '50s, 16" was
chosen as the wheel size. Dunlop had to make special tyres to this size. Tyre sizes
were 3.50/4.50-16 front and 3.75/6.00-16 rear. Dry weight was given as 130 kg. Rear
suspension was by swing arm with
monoshock (see picture right). The
pivoting point of the swinging arm
was in line with the engine sprocket which is good engineering practice
since it results in an even chain
tension throughout the swinging arm
travel. However, it necessitated the
mounting of the pivot point outside
the engine sprocket, which resulted in
a very long swinging arm, with the
cross bracing a rather long way
143
behind the pivot point, not really contributing to torsional stiffness.
The whole set-up of the monocoque frame proved a nightmare for the mechanics.
Simply to change the jets of the carburettors, the engine had to be supported, the tank
removed, and then the nine bolts holding the front part of the frame to the engine
removed. The front part could then be wheeled away, after removing of course all
cables, cooling hoses etc. (see pictures below). After changing the jets, the whole
operation was reversed.
Of course, if the change didn't have the desired effect, the whole thing started all over
again…. Not only that, but every time the frame was removed and put together again,
the bike felt and handled differently – because of the many bolts with their inherent
play and tolerances, the bike never went together as it had been before. Adding to the
problems was the fact that the frame kept on fracturing. Aluminium seemed simply
not the right material, or the design was wrong – tests with strain gauges should have
provided some answers.
144
The engine proved, contrary to the former racers, extremely unreliable and grossly
underpowered. Main problem areas were the piston "rings", which was to be
expected, and the valve springs, which had to cope with much heavier valves than
ever used by Honda at those engine speeds.
The racing, or rather the attempt at racing, with this bike was a disaster. As riders
Mick Grant and Takazumi Katayama were contracted. The first outing was
Silverstone in England, where Katayama qualified as 38th, and Mick Grant as 41st
didn't qualify, but
was first reserve.
However, he was
allowed a start
(pic. left) when
another
rider
withdrew.
Katayama's bike
started, but Grant
had
difficulties
getting it going.
When finally it
started,
Grant
made a wheelie
which, not known
to him, sprayed
oil
from
the
engine breather over the rear tyre. At the first corner this caused him to fall. Katayama
retired after the first lap with ignition and front brake problems. In Silverstone 28 mm
carburettors were tried, which gave a slight increase in power, but the acceleration
was worse, and the carburettors were changed back to 22 mm. The bikes produced
114 dB noise – the FIM limit was 115 dB.
145
The second race at Le Mans, France, the last race of the 1979 season, was an even
bigger debacle. Before the race the whole team returned to Japan to try and get more
power out of the engine, and they returned with a 108 PS engine, and a weight saving
of the whole bike of 5 kg. Power increase was realised, a.o., by changing the
carburettors to 26 mm with flat slides. (At the time, according to chief designer
Irimajiri, who had originally designed the six cylinder racers, the carburettors were a
source of a lot of problems, and he hinted that in future fuel injection would be tried.)
However, neither rider managed to qualify, and they were not allowed to start. The
new NR500 0X had proved, as a racing motorcycle, to be an abject failure. Honda had
violated the old tuners adage: never change more than one thing at a time – they had
practically left nothing unchanged.
For the 1980 season the engine was completely re-engineered with an aim of more
power and, maybe even more important, more reliability. The camshaft drive moved
from the right hand side of the engine to the middle. The included valve angle was
reduced to 55 degrees, and the compression ratio slightly raised to 10.7 : 1. The
crankshaft was now a built-up type with the crankpins press-fitted in the webs. At first
the sideways placing of the radiators was maintained – later they were replaced with
one radiator in front of the engine and one under the seat. This development work
resulted in 118 PS at 19,000 rpm at the beginning of 1980. Halfway through the year
122 PS was measured, the power gradually creeping to the goal of 130 PS.
1980 engine, dry clutch removed
The cycle parts, which had proved so unsatisfactory during 1979, were changed
radically. Initially the monocoque frame was used again, but with changed front forks
and brake calipers, now behind the fork legs, while the wheel spindle moved to a
position in front of the fork legs. The external springs were retained (see picture
below; photo by Sigeo Kibiki).
146
The frame was then changed to a tubular one,
initially made by Ron Williams of Maxton fame,
later by Honda themselves. The wheels were
changed to 18" Comstars, and subsequently
conventional telescopic front forks were used,
replacing the Honda types – at first Italian
Marzocchis, later Japanese Showas. However, the
weight had risen to 152 kg, of which some 65 kg
was on account of the engine.
This new version, the 1X, was first raced by Ron
Haslam and Mick Grant at Donington Park in
England, where Grant retired after only two laps,
and Haslam's engine blew up a couple of laps
before the end. Later, the bike was raced by
Katayama in a non-GP event in Misano, where it finished third. This lead the team to
decide to compete in the Finnish Grand Prix at Imatra one week later. However,
Katayama managed only to qualify in last place. Furthermore, during practice the
engine seized twice, and team manager Gerald Davison decided not to race the bike.
Two more Grand Prix were contested during 1980: Silverstone, where Katayama
finished 15th and last, and the German GP at the Nürburgring, where Katayama came
in 12th. See picture above. At last the bike started to be reliable enough to complete a
GP.
For 1981 the included valve angle was further reduced to 40 degrees, and the inlet
valves enlarged to 18.5 mm. Carburettor size was increased to 30 mm. The engine
was claimed to give now over 130 PS at 19,000 rpm. Later Soichiro Irimajiri said, that
the last version of the NR500 gave 130 PS at 21,600 rpm – to enable this, the stroke
was shortened to 30.6 mm. This enabled a larger piston area (See Appendix 1). See
147
pictures below – the reduced valve angle is clearly seen when compared to the
pictures of the 0X version
.
Picture left shows the
cylinder head of the 2X
version with the 8 valves
and two spark plugs per
cylinder. Here, too, the
shallow valve angle is
quite clear.
The picture right shows the elongated piston front,
top and bottom. It is not known whether there was
one long or two short gudgeon pins, the latter
option, being lighter, being the most obvious.
148
Two sectional drawings of the
engine. (The upper drawing is
confusing – there is only one
piston on each side of the central
gear drive to the camshafts).
According to this drawing, there
would have been one throughgoing gudgeon pin per piston,
which doesn’t seem logical.
Clearly the large size of the
carburettors can be seen – at 30
mm, the choke area of the
carburettors was 31 % larger than
that of the two 18.5 mm inlet
valves!
149
The picture above (photo J. Kortekaas) shows a section view of the NR500 engine.
The bifurcation of the inlet port can clearly be seen
The frame remained the steel tubular one, with Honda's pro-link rear suspension, but
front wheel size was reduced to 16" – tyre sizes 12/60-16 front and 16/70-18 rear. Dry
weight of the bike was given as 130 kg, of which 56 kg was the weight of the engine.
The NR500 2X as it won the Suzuka race (photo Honda Collection Hall)
150
The first race competed in was an All Japan Championship race in Suzuka, where
Katayama crashed and Kiyama, also NR500 mounted, ran into the fallen bike and also
fell off. One month later Kiyama came in 4th in another Japanese championship race.
In Holland, at an international race at Hengelo, Katayama retired. One week later, he
came in 13th in the European GP at the Salzburgring in Austria; in France Katayama
fell off after a split water hose had sprayed his rear tyre.
Katayama in France
Then, during the 6th Japan Championship race Kengo Kiyama came in first, with
Takeo Abe on a second NR500 in fourth position. So far as I know, this was the only
race ever won by the NR500 (see picture above, photo Honda Collection Hall).
Halfway through the year Freddie Spencer tested the NR500, and was 2 seconds faster
than anyone had ever ridden the NR around Suzuka.
At the Dutch TT at Assen, Katayama was holding 10th place, when an ignition failure
forced him to retire during the last lap. In Laguna Seca, Freddie Spencer's NR broke
the valve springs, because of over-revving. At the Silverstone GP, Spencer held 5th
place before retiring with a bust engine.
And that was it. Honda decided to stop the development of the NR500 and to opt for
two-strokes instead.
An era had ended.
Honda always maintained that the NR500 project was not so much about winning of
Grand Prix, but the development of new technology for the motorcycles of the future.
That might well have been the case, but then I think the whole project was still not
really a success; apart from one 750 cc race bike with oval pistons in 1987 (which
debuted in Le Mans, but failed to finish) and the prohibitively expensive NR750 street
bike of 1990, no engines with oval pistons were ever developed – and neither was
there ever a bike with monocoque frame. However, the whole project must have been
151
a very thorough exercise in motorcycle design for young engineers – and that can only
be beneficial for the future.
A turbo-charged 250 V-twin
Although in principle outside the scope of this book, it might be interesting to know,
that Honda later used half an NR500 engine to create a 250 cc V-twin. This engine
was supercharged with two turbo-chargers and was claimed to developed no less than
150 PS! See picture below.
Remarkable was, that while the NR500 had plain big-ends, this engine had roller
bearings. Instead of carburettors, fuel injection was used.
Honda stated, that the engine was developed with a view to enter it for the 1984 and
1985 Grand Prix – but that seems highly improbable, since supercharging was, and
still is, forbidden.
152
Appendix 1
Ways to increase power
Honda's meteoric rise from a totally unknown entity to a Grand Prix racing
dominating company has been a source of amazement to many people. First
competing only once in 1959 with 125 cc machines that were considered by the
Western critics to be outdated (although the concept of a twin cylinder in this class,
with the exception of the rather unsuccessful 125 cc Gilera twin, was new), then
competing with a reasonable amount of success a year later with 125 cc twins and 250
cc fours, and then to grab the 125 cc and 250 cc world titles one year thereafter, in
their only second full-time year of Grand Prix racing, was indeed a remarkable feat.
However, it is not so difficult to understand their swift success – they used scientists
and engineers (and with this I mean real, university trained engineers – not the often
glorified mechanics that the English and Americans so often call "engineers") to
design and develop racing engines to exacting scientific principles and engineering
standards, instead of using empirical and trial-and-error methods which most of the
European manufacturers used at that time. The results were engines that were superior
in their classes to anything else used so far, with the possible exception of the NSU
racers.
Use of short-stroke engines
Honda's first important step was the sole use of short stroke engines (with their one
exception, the RC144), which was not all that common when they started in the
fifties. The very successful 500 cc MV four-cylinder racers, for instance, went from a
square bore and stroke of 54 mm via a bore and stroke of 53 x 56.4 mm to 52 x 58
mm – the same bore and stroke of the four cylinder Gilera (which later changed to 52
bore x 58.8 stroke) on which the design of the MV was based. Other examples of long
stroke engines were the 125 cc MV world championship bikes (53 x 56 mm), the
Mondial 125 cc world champion bikes (53 x 56 mm), and the Benelli 250 cc single
(67 x 70 mm). Ing. Carcano, the genius engineer who designed the very successful
Moto Guzzi racers, used a mixture of long- and short stroke designs (e.g., his
revolutionary 8-cylinder 500 cc engine was a short stroke at 44 x 41 mm, but his 1957
350 cc world championship winning single-cylinder had a bore and stroke of 75 x 79
mm). The very successful NSU 125 cc Rennfox and 250 cc Rennmax racers were
short strokes – and probably that's why they were so successful. Even the Guzzis
couldn't catch them.
The use of a short stroke engine for maximum power production is imperative, and it
is amazing that so many manufacturers stuck so long to the long stroke design. Let's
see why that's amazing.
The general formula for power in a mechanical sense is:
N=FxS
In which:
N = power
F = force
S = speed
153
For an internal combustion engine, this translates to:
N = Pme x (π/4) x d2 x s x n x i x C
In which:
N
= power
Pme
= mean effective pressure
d
= bore
s
= stroke
n
= engine speed, rpm
i
= number of cylinders
C
= constant
The expression π/4 is a constant, and thus can be included in the constant C and
omitted from the equation. It should further be noted, that s x n/30 is the average or
mean piston speed Cm, and the 30 can again be included in C and omitted. We can
confine ourselves to a single cylinder (the principle holds for any number of
cylinders), so the i can be omitted too. The power formula thus reduces to:
N = Pme x d2 x Cm x C
As regards Pme, the Mean Effective Pressure, we can say that most manufacturers
more or less reached a maximum for their type of engine. Pme has an absolute
maximum anyway, because above a certain limit detonation will occur. We can
therefore say, without making a big error, that Pme can be considered a constant, and
be left out of the equation to be included in C. The same holds for the mean piston
speed Cm: above approximately 21 m/s, (this has to be viewed in the context of the
years we’re talking about – present day piston speeds are higher, but the principle
stays the same) the stresses on pistons, conrods and small-end- and big-end bearings
become so high, that reliability can no longer be guaranteed. Therefore, nearly all
racing engines of repute have a mean piston speed of between 19 and 22 m/s (lower
speeds, as is the case with most Honda GP engines, simply means that those engines
are not yet at the top of their development, but will be very reliable from a mechanical
point of view). Therefore we can state that Cm is also a constant, and be left out.
Consequently, we are then left with:
N = d2 x C
From this it follows, that for any well designed engine, with Pme and Cm to the limit,
the power is only dependent on d2, i.e., the bore squared, or, in other words, the piston
area. That means that for maximum power a successful engine has to be a short
stroke, with a bore which is as big as possible, within the constraints of providing
adequate support by the conrod, and thermal stresses. As regards the latter, with
increasing bore, the heat absorbing area rises in proportion with the piston area, so
with d2, while the heat dissipating area rises with the circumference of the piston, so
with d, and thus gives an increased thermal load for short-stroke engines. Of course
there are advantages (larger area to install larger valves) and disadvantages (greater
acceleration- and deceleration forces of the crankshaft mechanism, hence larger
stresses on conrods and bearings, larger side thrust from the piston). We can safely
say that all the disadvantages have been overcome.
154
The above principle was adequately proven by Honda themselves, through the abject
failure of their RC144 125 cc long-stroke engine. It is also proven by the fact, that
there is not a single racing engine manufacturer left in the world who builds a longstroke engine any longer. Those days are over.
The idea that short-stroke designs would give more power was already well known in
the fifties – but manufacturers went to short-stroke designs for completely the wrong
reasons (albeit with, of course, the right results) – as we shall see next.
The use of multi-cylinder engines
Time and again we've read in books and magazine articles, that the designers and
tuners of engines sought ever higher revolutions to increase power, and when the limit
was reached with regard to the allowable piston speed, they would divide the engine
capacity up in more cylinders, in order to shorten the stroke and so to allow a higher
engine speed.
This is a fallacy.
As we've seen above, in the simplified formula for power, the engine speed doesn't
appear – it is taken into account by the constant C, since the engine speed translates
into the mean piston speed, which is a constant. Let's analyse the real advantage of
dividing-up the engine capacity.
Let D and Vs be the bore and cylinder capacity of a single-cylinder engine, and d and
Vi the bore and capacity of one cylinder of a multi-cylinder engine with i cylinders
and the same total engine capacity as the single-cylinder engine. Let us furthermore
assume that the bore-to-stroke ratio, the mean effective pressure Pme and the mean
piston speed Cm of both engines are the same. For any given bore-to stroke ratio we
may now say:
Vs ≡ D3 x C (the symbol ≡ denotes " is proportional to"), and
Vi ≡ d3 x C
Since the constant C is the same in both equations, we can leave it out, whereupon our
already simple formulae reduce to:
V s ≡ D3
Vi ≡ d3
Since the multi-cylinder engine has i cylinders, it follows that one cylinder should
have a capacity of 1/i x Vs, so:
Vi = 1/i x Vs ≡ 1/i x D3 ≡ d3
d3 = 1/i x D3 → d =(1/i)1/3 x D
Piston area is proportional to the bore squared, so the total piston area of the multicylinder engine with i cylinders and with bore d is, when compared to the singlecylinder engine:
Piston area = d2 x i = {(1/i)1/3 x D}2 x i = i1/3 x D2
155
So it transpires that the total piston area of a multi-cylinder engine is equal to the cube
root of the number of cylinders times the piston area of the single-cylinder engine.
From this simple statement we can now calculate, for various numbers of cylinders,
the increase in piston area compared to a single-cylinder.
Piston area of a:
Single
Twin
Triple
Four
Five
Six
Eight
= D2
= 1.26 D2
= 1.44 D2
= 1.58 D2
= 1.71 D2
= 1.81 D2
= 2.00 D2
Since the power of any given engine is, as we have seen, directly proportional to the
total piston area, the power of multi-cylinder engines should also increase with the
same amounts as the piston area. However, although the figures for the piston area as
given above hold perfectly true, the increase in power will no doubt be less, since
other factors (amongst others the mechanical efficiency) also play an important role.
Nevertheless, from the table above we can immediately see that it is the dramatic
increase in piston area for the multi-cylinder engine that gives it its increase in power.
That is precisely why Honda increased their number of cylinders. The higher engine
speed in revolutions per minute is merely the result of keeping the mean piston speed
at its maximum, combined with a reduced stroke – the product of stroke and engine
speed, i.e., the mean piston speed, remains the same, is constant. It also makes it clear,
that increasing the stroke of an engine is only meaningful as a means to increase
power if the mean piston speed is still below its safe limit. If the maximum piston
speed would be surpassed, then no power increase would be realised, since an
increase in stroke would require an inverse proportional decrease in engine speed.
Four valves per cylinder
Soichiro Honda realized, after his visit to the Isle of Man in 1954, that to win races his
motorcycles would have to have lots of power, for the competing European bikes like
NSU, MV, Mondial, Ducati and Guzzi were definitely no dawdlers.
Engine power is delivered according to the above given formula, which can also be
written as:
N = Pme x Vc x n x i x C
In which:
N
= power
Pme
= mean effective pressure
= capacity of one cylinder
Vc
n
= engine speed, rpm
i
= number of cylinders
C
= constant
156
Since the cylinder capacity is determined per class, the only way to increase power is
to increase the mean effective pressure Pme and the engine speed n. Pme is, a.o.,
dependent on the volumetric efficiency, or cylinder filling, and with rising engine
speed, so with rising rpm, the cylinder filling decreases, because with rising engine
speed the average speed of the gasses rises proportional to the engine speed, but the
resistance these gasses experience rises with the square of the speed.
The maximum attainable engine speed, apart from mechanical constraints (mean
piston speed), is dependent on the cylinder capacity, the effective inlet valve area, the
speed of sound and the so-called Mach-index, which latter entity is given by the
equation:
Ms = n x Vc/(30 x a x Ae)
In which:
Ms
n
Vc
a
Ae
d
Cms
= Mach-index
= engine speed, rpm
= capacity of one cylinder
= speed of sound
= effective inlet valve area, defined as: Ae = (π/4)d2.Cms , where
= valve diameter
= flow factor
The value of the Mach-index should stay below 0.5 – 0.6, since otherwise the
volumetric efficiency, and with it engine power, would fall-off sharply. Since engine
capacity and speed of sound are a given, Ms can only be kept low by choosing the
lowest possible engine speed and the largest possible effective inlet valve area.
However, the engine speed we want to have as high as is possible, the limitation being
the mean piston speed and hence the mechanical stresses (see the above), and so the
only possibility of obtaining a low value of Ms is enlarging Ae, the effective inlet
valve area. This means enlarging the valve diameter and improving the flow factor.
The latter can be attained by choosing the shape of the inlet port, the valve and the
valve seat such, that the in-flowing mixture experiences the least possible resistance.
Enlarging the valve diameter soon reaches a limit – in addition, large valves lead to
large valve angles, which, with a sufficiently high compression-ratio, leads to a very
unfavourable shape of the combustion chamber because of the high-domed piston.
Another disadvantage is the necessary, sideways placement of the spark plug, unless
two spark plugs per cylinder are used to get symmetrical combustion.
Honda’s approach of four valves per cylinder was therefore an obvious one. The
construction has numerous advantages and very few disadvantages. The two main
advantages are:
a. The effective inlet valve area increases considerably, even though the flow
factor decreases somewhat because of mutual influencing of the two inlet
flows. The maximum attainable engine speed for a two valve head with
hemispherical combustion chamber shape and a four-valve head with a roof
shaped combustion chamber is shown in figure "Attainable rpm".
b. Because of the smaller mass per valve, the desired high engine speeds can be
attained with a much reduced risk of valve float or valve bounce.
157
Additional advantages, which are also important, are the following:
a. The light valves allow the use of long, thin valve stems, which in turn leads to
favourably shaped inlet ports, without the valve guidance being endangered;
b. The roof-shaped combustion chamber becomes very compact and the spark
plug can be placed centrally;
c. The piston top can be flatter, and hence the piston will be lighter and thermally
will be loaded less because the heat absorbing area will be smaller;
d. The two relatively small exhaust valves are loaded thermally much less than
one big one.
The latter two points are important for the reliability of the engine.
The only disadvantages of the system are the higher fabrication costs and the more
time consuming adjusting and grinding of the valves.
Attainable rpm
158
Appendix 2
Inertia and pulsation effects
The length of inlet- and exhaust systems plays a very important role in the power
development of engines. Inertia-effect and wave or pulsation effect have both a strong
influence on volumetric efficiency.
The inlet system
1. The inertia effect
When an amount of gas, representing a certain mass, moves with a high velocity, it
will try to continue to do so, even if counter forces are working on it. It is therefore
that inlet valves close well after bottom dead centre (abdc), when the piston is already
rising in the compression stroke. This is what is meant by the "inertia-effect".
According to prof. Tsuyoshi Asanuma of the University of Tokyo, the inertia effect is
influenced by three factors:
a. The inertia-supercharging index Z
b. Flow restrictions in the inlet system
c. The inlet valve closing angle abdc
The value of the inertia-supercharging index Z is a function of the inlet valve closure
angle in degrees after bottom dead centre. The inlet length for optimum inertia effect
is now given by:
L = Zθ2 x Ae x a2 x C/(Vc x n2)
in which:
L
= inlet length
= inertia-supercharging index at inlet valve closure angle θ under
Zθ
consideration
Ae
= effective inlet valve area (see Appendix 1)
a
= speed of sound
C
= constant
Vc
= capacity of one cylinder
n
= engine speed, rpm
By employing the right inlet length, volumetric efficiencies of more than 100 % can
be achieved – hence the term supercharging index.
2. The pulsation effect
When the inlet valve closes, this will cause a positive wave to travel through the inlet
system towards the opening of the carburettor. When it reaches this opening, it will be
reflected with a negative sign, i.e., the wave will be reflected as a negative wave.
When it reaches the (still closed) inlet valve, it will be reflected with a positive sign,
i.e., the wave will stay negative and will travel towards the open end again. Here it
will again be reflected with a negative sign, and so now it will travel to the inlet valve
as a positive wave (a negative times a negative yields a positive). We want a positive
159
wave at the inlet valve when this is open and the piston is in its top dead centre (tdc)
to give an extra boost to the cylinder filling, so, in order to achieve this, the wave has
to travel at least 4 times to and fro through the inlet system to arrive in a usable form,
i.e., positive, at the inlet valve, but 8 times, 12 times and so on is also usable, since in
all those cases the wave will arrive positive. The number of times this process of 4
times to and fro, or one cycle, occurs, we call the order of pulsation q, so for 4 times q
= 1, for 8 times q = 2, for 12 times q = 3, and so on.
By choosing the right inlet length and order of pulsation q, we can achieve the
synchronization of the positive wave with the arrival of the piston in tdc of the next
inlet stroke, which will result in an increase of volumetric efficiency. If we combine
the inertia effect and pulsation effect by choosing the right inlet length and valve
timing, volumetric efficiencies of 120 % can be achieved.
The exhaust system.
In the exhaust system inertia effects and pulsations effects also play a significant role.
In this case we want a negative wave or pulse at the moment of valve overlap with the
piston in tdc to assist the inlet process. Shape and length of the megaphone also play a
role.
1. Inertia effect.
The exhaust valve already opens before the bdc, when the piston is still on its way
down, but because of the relatively high pressure of the burnt charge (approx. 5 barg),
the gas will start to flow out of the cylinder.
When the piston changes its direction to an upwards movement, the velocity of the
gas will increase, while the pressure drop of the gas will even add to the velocity.
The inertia of the high velocity gas is the cause that the column of gas will continue
flowing at the same speed, even when the piston speed at the end of the stroke will
decrease and even when the piston changes direction and starts to descend. Because of
this an under-pressure or suction will develop above the piston which will assist the
upwards movement of this part and will forcefully assist the start of the inlet process,
since the inlet valve opens before the tdc, when the exhaust valve is still open.
From the above it is clear, that the higher the exhaust gas velocity, the higher the
inertia or extraction effect will be, and this would require small-diameter exhaust
pipes. However, when exhaust pipes become smaller in diameter, at high engine
speeds the resistance for the exhaust gasses will increase, so a compromise has to be
found.
2. Pulsation effect.
When the exhaust valve opens, a positive wave starts to run down the exhaust pipe at
sound velocity (which, due to the higher temperature, is much higher than the sound
velocity in the inlet system). At the open end, this wave is reflected as a negative
wave towards the exhaust valve. Here we exactly want a negative wave (suction) at
the moment that the piston is in the tdc to assist the induction of fresh mixture via the
meanwhile opened inlet valve. However, letting the wave run just twice to and fro
would give an unusable long exhaust system, (compare q=1 for the inlet system) so
we let the wave reflect at the valve – at this, for the wave closed end (because there is
still a relatively high pressure), it will reflect with the same sign, i.e., negative. When
160
the wave now arrives at the open end, it will be reflected as a positive wave, at the
valve it reflects again as a positive wave, while at the open end it will change again to
a negative wave, in which usable form it will finally arrive at the exhaust valve. In
total the wave thus has run six times to and fro (six times the length of the exhaust
pipe).
At the open end the wave is reflected rather abruptly. When a megaphone is added to
the open end, it has the same effect as an open end that in little steps gets bigger, each
step reflecting part of the wave – and the result is a reflected wave with a more
"stretched" character, and which is consequently operative over a wider engine speed
range.
161
Appendix 3
Honda Grand Prix results per year
1959
Man
125 cc: 6 N. Taniguchi, 7 G. Suzuki, 8 J. Suzuki, 11 T. Tanaka.
1960
Man
125 cc: 6 N. Taniguchi, 7 G. Suzuki, 8 S. Shimazaki, 9 T. Tanaka, 10
T. Phillis, 19. M. Kitano.
250 cc: 4 R. Brown, 5 M. Kitano, 6 N. Taniguchi.
Assen
125 cc: 4 J. Redman.
250 cc: 7 J. Huberts, 8 J. Redman.
W. Germany 250 cc: 3 T. Tanaka, 6 K. Takahashi.
Ulster
250 cc: 2 T. Phillis, 3 J. Redman, 5 K. Takahashi.
Monza
125 cc: 4 J. Redman.
250 cc: 2 J. Redman.
1961
Spain
125 cc: 1 T. Phillis, 3 J. Redman.
250 cc: 2 T. Phillis, 4 J. Redman.
W. Germany 125 cc: 5 L. Taveri, 6 K. Takahashi, 7 J. Redman.
250 cc: 1 K. Takahashi, 2 J. Redman.
France
125 cc: 1 T. Phillis, 3 J. Redman, 5 L. Taveri, 6 K. Takahashi.
250 cc: 1 T. Phillis, 2 M. Hailwood, 3 K. Takahashi, 6 J. Redman.
Man
125 cc: 1 M. Hailwood, 2 L. Taveri, 3 T. Phillis, 4 J. Redman 5 S.
Shimazaki, 8 M. Taniguchi.
250 cc: 1 M. Hailwood, 2 T. Phillis, 3 J. Redman, 4 K. Takahashi, 5 N.
Taniguchi.
Assen
125 cc: 1 T. Phillis, 2 J. Redman, 8 J. Huberts
250 cc: 1 M. Hailwood, 2 R. McIntyre, 3 J. Redman
Belgium
125 cc: 1 L. Taveri, 2 J. Redman, 3 T. Phillis.
250 cc: 1 J. Redman, 2 T. Phillis
East Germany 125 cc: 2 T. Phillis, 3 K. Takahashi.
250 cc: 1 M. Hailwood, 2 J. Redman, 3 K. Takahashi, 4 T. Phillis.
Ulster
125 cc: 1 K. Takahashi, 3 T. Phillis, 4 J. Redman, 5 M. Hailwood, 6 L.
Taveri, 7 T. Tanaka.
250 cc: 1 R. McIntyre, 2 M. Hailwood, 3 J. Redman, 4 T. Phillis, 6 K.
Takahashi.
Monza
125 cc: 1 T. Tanaka, 2 L. Taveri, 3 T. Phillis.
250 cc: 1 J. Redman, 2 M. Hailwood, 3 T. Phillis.
Sweden
125 cc: 1 L. Taveri, 2 K. Takahashi, 3 J. Redman, 6 T. Phillis.
250 cc: 1 M. Hailwood, 2 L. Taveri, 3 K. Takahashi, 4 J. Redman, 6 T.
Phillis.
Argentina
125 cc: 1 T. Phillis, 2 J. Redman, 3 K. Takahashi, 4 S. Shimazaki, 5 N.
Taniguchi.
250 cc: 1 T. Phillis, 2 K. Takahashi, 3 J. Redman.
1962
Spain
50 cc: 3 L. Taveri, 5 T. Robb, 6 K. Takahashi, 8 T. Phillis.
125 cc: 1 K. Takahashi, 2 J. Redman, 3 L. Taveri.
162
250 cc: 1 J. Redman, 2 R. McIntyre, 3 T. Phillis.
50 cc: 2 K. Takahashi, 3 L. Taveri, 4 T. Robb.
125 cc: 1 K. Takahashi, 2 J. Redman, 3 T. Robb, 4 L. Taveri.
Man
50 cc: 2 L. Taveri, 3 T. Robb
125 cc: 1 L. Taveri, 2 T. Robb, 3 T. Phillis, 4 D. Minter, 5 J. Redman.
250 cc: 1 D. Minter, 2 J. Redman, 3 T. Phillis.
Assen
125 cc: 1 L. Taveri, 2 J. Redman, 3 T. Robb.
250 cc: 1 J. Redman, 2 R. McIntyre, 4 C. Swart
350 cc: 1 J. Redman.
Belgium
50 cc: 3 L. Taveri.
125 cc: 1 L. Taveri, 2 J. Redman.
250 cc: 1 R. McIntyre, 2 J. Redman, 3 L. Taveri.
W. Germany 50 cc: 4 L. Taveri, 7 T. Robb.
125 cc: 1 L. Taveri, 2 T. Robb, 4 R. McIntyre.
250 cc: 1 J. Redman, 2 R. McIntyre, 3 K. Tanaka, 4 G. Beer
Ulster
125 cc: 1 L. Taveri, 2 T. Robb, 3 J. Redman, 4 K. Tanaka.
250 cc: 1 T. Robb, 2 J. Redman, 3 L. Taveri.
350 cc: 1 J. Redman, 3 T. Robb.
East Germany 50 cc: 4 L. Taveri, 5 T. Robb, 7 T. Tanaka.
125 cc: 1 L. Taveri, 2 J. Redman, 4 T. Robb.
250 cc: 1 J. Redman.
350 cc: 1 J. Redman, 3 T. Robb.
Monza
50 cc: 6 L. Taveri.
125 cc: 1 T. Tanaka, 2 L. Taveri, 3 T. Robb, 4 J. Redman.
250 cc: 1 J. Redman, 4 M. Kitano.
350 cc: 1 J. Redman, 2 T. Robb.
Finland
50 cc: 1 L. Taveri, 2 T. Robb, 5 T. Tanaka.
125 cc: 1 J. Redman, 2 L. Taveri.
350 cc: 1 T. Robb, 2 J. Redman, 6 M. Kitano.
France
1963
Spain
125 cc: 1 L. Taveri, 2 J. Redman, 3 K. Takahashi.
250 cc: 2 J. Redman, 3 T. Robb, 4 K. Takahashi, 5 L. Taveri.
W. Germany 125 cc: 4 L. Taveri, 5 K. Takahashi, 7 T. Robb.
50 cc: 2 T. Robb, 3 J. Redman.
350 cc: 1 J. Redman.
France
125 cc: 2 J. Redman, 3 L. Taveri, 5 T. Robb.
Man
125 cc: 4 L. Taveri, 6 J. Redman, 7 T. Robb, 8 K. Takahashi.
250 cc: 1 J. Redman, 5 T. Robb.
350 cc: 1 J. Redman.
Assen
125 cc: 3 L. Taveri, 5 K. Takahashi, 6 T. Robb.
250 cc: 1 J. Redman, 5 T. Robb.
350 cc: 1 J. Redman, 3 L. Taveri.
Belgium
125 cc: 3 L. Taveri, 5 T. Robb.
250 cc: 4 L. Taveri, 5 T. Robb, 6 K. Takahashi.
Ulster
125 cc: 3 L. Taveri, 4 T. Robb, 5 K. Takahashi, 7 J. Redman.
250 cc: 1 J. Redman, 3 T. Robb, 4 K. Takahashi.
350 cc: 1 J. Redman, 3 L. Taveri.
East Germany 125 cc: 4 L. Taveri, 7 J. Redman, 8 K. Takahashi.
250 cc: 3 J. Redman, 5 L. Taveri, 7 T. Robb.
350 cc: 2 L. Taveri, 3 J. Redman.
163
Finland
Monza
Argentina
Japan
125 cc: 2 L. Taveri, 5 J. Redman.
350 cc: 2 J. Redman, 5 L. Taveri.
125 cc: 1 L. Taveri, 2 J. Redman, 3 K. Takahashi, 7 T. Robb.
250 cc: 2 J. Redman, 3 L. Taveri, 6 T. Robb.
125 cc: 1 J. Redman.
250 cc: 2 J. Redman.
50 cc: 1 L. Taveri, 5 S. Shimazaki, 8 T. Robb.
125 cc: 2 J. Redman, 4 T. Robb.
250 cc: 1 J. Redman, 5 L. Taveri.
350 cc: 1 J. Redman, 2 M. Yamashita, 3 L. Taveri.
1964
Spain
125 cc: 1 L. Taveri, 2 J. Redman.
250 cc: 2 J. Redman.
France
125 cc: 1 L. Taveri, 4 K. Takahashi.
250 cc: 2 L. Taveri, 4 B. Beale.
Man
50 cc: 2 R. Bryans, 6 N. Taniguchi.
125 cc: 1 L. Taveri, 2 J. Redman, 3 R. Bryans, 6 B. Beale.
250 cc: 1 J. Redman.
350 cc: 1 J. Redman.
Assen
50 cc: 1 R. Bryans.
125 cc: 1 J. Redman, 3 R. Bryans.
250 cc: 1 J. Redman, 7 B. Beale.
350 cc: 1 J. Redman.
Belgium
50 cc: 1 R. Bryans.
250 cc: 2 J. Redman, 7 B. Beale.
W. Germany 50 cc: 1 R. Bryans.
125 cc: 1 J. Redman, 2 L. Taveri.
250 cc: 2 J. Redman, 6 L. Taveri.
350 cc: 1 J. Redman, 2 B. Beale.
East Germany 125 cc: 2 L. Taveri, 3 J. Redman, 6 B. Beale.
250 cc: 2 J. Redman, 3 B. Beale.
350 cc: 1 J. Redman, 4 B. Beale.
Ulster
125 cc: 2 L. Taveri, 3 R. Bryans, 7 B. Beale.
250 cc: 2 J. Redman, 3 R. Bryans, 5 B. Beale.
350 cc: 1 J. Redman, 4 B. Beale.
Finland
125 cc: 1 L. Taveri, 2 R Bryans, 3 J. Redman.
350 cc: 1 J. Redman, 2 B. Beale.
Monza
125 cc: 1 L. Taveri, 4 R. Bryans, 6 J. Redman.
250 cc: 3 J. Redman, 6 L. Taveri.
350 cc: 1 J. Redman, 2 B. Beale.
Japan
50 cc: 1 R. Bryans, 2 L. Taveri, 3 N. Tanaguchi.
125 cc: 2 L. Taveri, 4 T. Tanaka.
250 cc 1 J. Redman, 2 I. Kasuya, 4 L. Taveri.
350 cc: 1 J. Redman, 3 I. Kasuya, 4. M. Yamashita, 5 K. Nagamatsu.
1965
W. Germany 50 cc: 1 R. Bryans, 2 L. Taveri.
Spain
50 cc: 2 R. Bryans, 4 L. Taveri.
France
50 cc: 1 R. Bryans, 2 L. Taveri.
250 cc: 2 B. Beale.
164
Man
50 cc: 1 L. Taveri.
125 cc: 2 L. Taveri, 6 R. Bryans.
250 cc: 1 J. Redman.
350 cc: 1 J. Redman, 4 B. Beale.
Assen
50 cc: 1 R. Bryans, 3 L. Taveri.
125 cc: 5 L. Taveri.
250 cc: 2 J. Redman, 5 B. Beale.
350 cc: 1 J. Redman.
Belgium
50 cc: 3 L. Taveri.
250 cc: 1 J. Redman, 6 B. Beale.
East Germany 250 cc: 1 J. Redman.
350 cc: 1 J. Redman.
Czechoslovakia
250 cc: 3 J. Redman.
350 cc: 1 J. Redman.
Ulster
125 cc: 4 R. Bryans, 5 B. Beale.
250 cc: 5 R. Bryans.
350 cc: 2 B. Beale.
Japan
50 cc: 1 L. Taveri, 2 R. Bryans.
125 cc: 2 L. Taveri, 3 R. Bryans.
250 cc: 1 M. Hailwood, 2 I. Kasuya, 4 M. Yamashita.
350 cc: 2 J. Redman, 3 I. Kasuya, 4 M. Yamashita.
1966
Spain
50 cc: 1 L. Taveri, 3 R. Bryans.
125 cc: 2 L. Taveri, 3 R. Bryans.
250 cc: 1 M. Hailwood.
W. Germany 50 cc: 2 R. Bryans, 4 L. Taveri.
125 cc: 1 L. Taveri, 2 R. Bryans.
250 cc: 1 M. Hailwood, 2 J. Redman.
350 cc: 1 M. Hailwood, 3 B. Beale.
500 cc: 1 J. Redman.
France
250 cc: 1 M. Hailwood, 2 J. Redman.
350 cc: 1 M. Hailwood, 3 J. Redman.
Assen
50 cc: 1 L. Taveri, 2 R. Bryans.
125 cc 2 L. Taveri.
250 cc: 1 M. Hailwood, 3 J. Redman.
350 cc: 1 M. Hailwood.
500 cc: 1 J. Redman.
Belgium
250 cc: 1 M. Hailwood, 3 J. Redman.
East Germany 125 cc: 1 L. Taveri, 6 R. Bryans.
250 cc: 1 M. Hailwood, 4 S. Graham.
Czechoslovakia
125 cc: 1 L. Taveri, 2 R. Bryans.
250 cc: 1 M. Hailwood.
350 cc: 1 M. Hailwood.
500 cc: 1 M. Hailwood.
Finland
125 cc: 2. L. Taveri, 3 R. Bryans.
250 cc: 1 M. Hailwood, 2 S. Graham.
350 cc: 1 M. Hailwood, 5 B. Beale.
500 cc: 2 M. Hailwood.
165
Ulster
Man
Monza
125 cc: 1 L. Taveri, 2 R. Bryans.
350 cc: 1 M. Hailwood.
500 cc: 1 M. Hailwood.
50 cc: 1 R. Bryans, 2 L. Taveri.
125 cc: 6. M. Hailwood.
250 cc: 1 M. Hailwood, 2 S. Graham.
500 cc: 1 M. Hailwood.
50 cc: 2 R. Bryans, 3 L. Taveri.
125 cc 1 L. Taveri, 2 R. Bryans.
250 cc: 1 M. Hailwood, 5 B. Beale.
1967
Spain
250 cc: 2 R. Bryans.
W. Germany 250 cc: 1 R. Bryans.
350 cc: 1 M. Hailwood.
France
250 cc: 3 M. Hailwood, 4 R. Bryans.
Man
250 cc: 1 M. Hailwood, 3 R. Bryans.
350 cc: 1 M. Hailwood.
500 cc: 1 M. Hailwood.
Assen
250 cc: 1 M. Hailwood, 3 R. Bryans.
350 cc: 1 M. Hailwood.
500 cc: 1 M. Hailwood.
Belgium
250 cc: 2 M. Hailwood, 3 R. Bryans.
500 cc: 2 M. Hailwood.
East Germany 250 cc: 3 R. Bryans.
350 cc: 1 M. Hailwood.
Czechoslovakia
250 cc: 3 M. Hailwood, 4 R. Bryans.
350 cc: 1 M. Hailwood.
500 cc: 1 M. Hailwood.
Finland
250 cc: 1 M. Hailwood.
Ulster
250 cc: 1 M. Hailwood, 2 R. Bryans.
350 cc: 2 R. Bryans.
500 cc: 1 M. Hailwood.
Monza
250 cc: 3 R. Bryans.
350 cc: 1 R. Bryans.
500 cc: 2 M. Hailwood.
Canada
250 cc: 1 M. Hailwood, 3 R. Bryans
500 cc: 1 M. Hailwood
Japan
250 cc: 1 R. Bryans.
350 cc: 1 M. Hailwood, 2 R. Bryans.
1980
Silverstone 500 cc: 15 T. Katayama
W. Germany 500 cc: 12 T. Katayama
1981
Austria
500 cc: 13 T. Katayama
166
1
6
7
1
6
8
1
6
9
1
7
0
1
7
1
1
7
3
Bibliography
Bacon, Roy: Honda – The Early Classic Motorcycles. Niton Publishing, 1996. ISBN
1-85579-028-9
Bejot, Jean-Pierre: Honda. PAC, 1976. (in French)
Carrick, Peter: The Story of HONDA Motorcycles. Patrick Stevens Ltd, 1976. ISBN
0-85059-243-7
Cathcart, Alan: The Ultimate Racers. Guinness Publishing, 1990. ISBN 0-85112-9161.
Exciting Bike – Honda Story. 1991. (in Japanese)
Hailwood, Mike and Murray Walker: The Art of Motorcycle Racing. Cassell, 1963.
Hailwood, Mike and Ted Macauley: Hailwood. Cassell, 1968, SBN 304-93240-x
History of Japanese Racing Motorcycles. (in Japanese)
Honda Collection 1: Challenge and Creation. Neko Publishing Co. Ltd. (in Japanese,
some English)
Honda Collection 2: A Passion for Motor Sports. Neko Publishing Co. Ltd. (in
Japanese, some English)
Honda Sports Bike Spirit. Motor Graphic Series, 1990. ISBN 4-404-01686-7 (in
Japanese)
MacKeller, Colin: Honda GP racers. The Crowood Press, 1998. ISBN 1-86126-073-3
Masaaki, Sato: The Honda Myth. Vertical Inc., 2006. ISBN 978-1-932234-26-8
Nakamura, Yoshio, Honda R & D Co., Ltd.: Small High-Speed, High-Performance
Gasoline Engine. SAE Paper.
Redman, Jim: Jim Redman MBE – Six Times World Motorcycle Champion – The
Autobiography. Veloce Publishing PLC, 1998. ISBN 1-901295-35-4
Sakiya, Tetsuo: Honda Motor. Kodansha International, 1989. ISBN 0-87011-697-5
Sanders, Sol: Honda. Little, Brown and Company, 1975. ISBN 0-316-77007-8
Willoughby, Vic: The Racing Motor Cycle. Hamlyn, 1980. ISBN 0-600-36342-2.
Woollett, Mick: Honda Racers in the Golden Age. Neko Publishing Co., Ltd, 1990.
ISBN 4-87366-063-7 (in Japanese and English)
Yagi, Shizuo, Ishizuya, Akira and Fujii, Isao, Honda R & D Co., Ltd: Research and
Development of High-Speed, High Performance, Small Displacement Honda Engines.
SAE Paper.
Index
2RC143, 33,34,167
2RC146, 64,67,71, 168
2RC164, 66, 169
2RC172, 74
3RC164, 66, 73, 74, 169
4RC146, 67, 71
Abe, T., 151
AerMacchi, 76, 88, 102, 122
Agostini, G., 68, 69, 76, 77, 88,
104, 105, 119
AJS, 63, 122
Anderson, H., 60, 62, 67, 68
Anscheidt, H-G., 41, 42, 62, 75
Argentina, 32
Asanuma, Prof. T., 159
Assen, 24, 25, 32, 35, 41, 43, 62,
68, 77, 88, 98, 100, 105, 133, 136,
151
Austria, 136, 151
Autodromo Santamonica, 131
Avon, 102
Bakker, N., 130
Baldwin, 132, 138, 139, 140
Barcelona, 75, 86, 123, 128, 131,
133, 136
Bardi, 128
Beale, B., 63
Belgian GP, 98
Belgium, 32, 68, 77, 78, 105, 123,
126, 128
Belletti, 102
Benelli, 18, 40. 88, 96, 102, 122,
153
Bianchi, 18, 35
Bol d'Or, 115, 119, 122, 123, 128,
131, 133, 135, 137-139
Bowler, R., 122, 123
Bridgestone, 96
B.R.S.C., 138
Bryans, R., 62. 67, 68, 75, 86, 88,
100, 101, 119
Brno, 98
Brown, B., 24, 98
BSA, 15, 119
Bultaco, 76, 87
Burki, 128
Buytaerts, J., 128
Camathias, F., 59
Canada, 89
Carcano, 80, 153
Carruthers, K., 40
Cathcart, A., 103, 104
CB72/77, 28-31, 56
CB92, 16, 29, 30
CB350, 96, 107
CB350R, 107
CB450, 21, 31, 36, 116, 117
CB500, 96, 113, 114
CB500R, 114, 172
CB750R, 111
CB900F, 136, 138
Ceriani, 102
Chemarin, J-C., 123, 128, 131-137,
139
Clermont-Ferrand, 86
Comstar, 126, 143, 147
Cooley, 132, 136
Coudray, 133, 136, 139
CR71, 20, 171
CR72, 23, 29, 48, 55-58, 99, 172
CR77, 23, 29, 48, 55, 57, 58, 60, 63,
99, 107, 172
CR93, 21, 28, 29, 48, 51-55, 57, 58,
171
CR110, 21, 23, 29, 48-51, 55, 58,
70, 171
CR250, 57
CR305, 57
CR450, 113, 116, 117, 172
CYB350, 107, 108, 172
Czechoslovakia, 68
Dähne, H., 128, 131, 133, 136, 137
Davison, G., 147
Daytona, 67, 68, 96, 109, 116, 119122
Degner, E., 24, 32, 41
Donington Park, 147
Duff, M., 63, 68, 69
Dunlop, 102, 143
Dutch TT, 24, 32, 98, 103, 104, 151
Dyrda, 128, 133
East-Germany, 17, 32, 67-69, 77,
86
EMC, 32
Evans, P., 123
Ferrari, V., 136
Ferreira, 128
Finland, 41, 43, 69, 86
Fisco, 75
Fontan, M, 136, 137
Formula 1, 7, 60, 67, 119
Fox, 17
France, 10, 32, 67, 68, 122, 128,
138, 139, 146, 151
Francorchamps, 67, 76, 78, 84, 86,
98, 104, 123, 139
French GP, 43, 100
Fujisawa, T., 9, 10
George, A., 123
German GP, 33, 147
, 10, 24, 32, 67, 68, 76, 86, 98, 104,
126 Gilera, 18, 59, 97, 100, 153
Girling, 28, 102, 106
Graham, S., 75, 97, 101
Grant, M., 145, 147
Grant, R., 119
Grau, B., 128, 131
Green, G., 128, 131, 132, 137
Gross, 137
Guillou, J-L., 122, 138, 139
RCB1000, 124, 136, 173
Hailwood, M., 32, 33, 41, 60, 66,
68, 69, 75-78, 80, 85-88, 97-106,
119
Hailwood, S., 78, 99
Hansen, B., 116, 119
Harley Davidson, 9, 116, 119
Hartle, J., 88, 99, 103
Haslam, R., 147
Hocking, G, 24, 25, 32, 41
Hodder, A., 103
Holland, 33, 67, 76, 95, 126, 151
Honda, S., 9, 10, 12, 17, 33, 40
Hout, H. v.d., 128
Hubin, 133, 137
Huguet, C., 123, 128, 133, 137, 139
Hunt, B, 15, 16, 97
Hybrids, 40
Inertia, 159, 160
Irimajiri, S., 146, 147
Isle of Man, IoM: see Man
Itoh, F., 60
Ivy, B., 75, 86, 87
Jawa, 41, 76, 96, 122, 143
Katayama, T., 145, 147, 151
Kawasaki, 96, 119, 131-133, 136,
137, 139
Kawashima, K., 99
Kei-hin, 15, 27, 28, 34, 82, 107,
109, 117, 120, 125, 130, 138
Kitano, M., 99
Kiyama, K., 151
Korhonen, P., 128
Kreidler, 41, 62, 75
Leon, C., 122, 123, 128, 131-137
Le Mans, 123, 131, 133, 136, 139,
146, 151
Liege, 123, 128, 131, 133, 137
Luc, J., 128, 131-133, 139
Lyster, C., 102
Mach-index, 157
Maingret, 128
Mallol, 136
Man, 9, 10, 15, 28, 33, 41, 43, 46,
68, 75, 87, 96, 98-100, 105, 156
Mann, D., 119
Marshall, 128
Matchless, 77, 88, 116, 119, 122
Maxton, 147
McIntyre, B., 32, 35, 41, 99, 100,
102, 103
Mettet, 132
Minter, D., 100
Misano, 128, 131, 137, 147
Moineau, H., 133, 136, 137
Mondial, 17, 102, 153, 156
Monin, 137
Monocoque, 143, 144, 146, 151
Monza, 25, 32, 40, 59, 60, 63, 68,
73, 77, 85, 86, 100
Mooster, 128
Morini, 60, 102
Mugello, 123
Murray, 132
Murray's Museum, 33
MV, 24, 25, 32, 41, 60, 66, 68, 69,
74-77, 88, 96, 97, 99, 100, 102, 104,
105, 119, 122, 153, 156
MZ, 24, 32, 63, 66, 76, 87, 88, 122
Nixon, G., 119
Nokamura, 119
Norton, 34, 41, 100, 122NR500,
141, 146, 147, 150-152, 174
NSU, 17, 153, 156
Nürburgring, 128, 131, 133, 134,
136, 139, 147
Odom, J., 116
Oudin, 133, 136, 139
Pasolini, R., 76
Paul Ricard, 128
Perris, F., 61, 68
Peyre, J-B., 136
Phillis, T., 24, 25, 28, 32, 41, 98,
102, 103
Pons, P., 131-133
Puch, 141
Pulsation, 159, 160
Rayborn, C., 119
Read, P., 62, 63, 67-69, 75, 76, 78,
86, 87, 98, 103
RC71, 19, 20, 171
RC110, 42, 48, 167
RC111, 42, 43, 167
RC112, 21, 42, 43, 63, 100, 167
RC113, 61, 63, 64, 66, 167
RC114, 63, 64, 70, 167
RC115, 70, 79, 167
RC116, 79, 80, 167
RC140, 11
RC141, 12, 15
RC142, 12, 15, 17, 25, 167
RC143, 25, 26, 28, 33, 34, 167
RC144, 21, 33, 153, 155
RC145, 44, 45, 60, 168
RC146, 61, 64
RC148, 71, 79, 168
RC149, 22, 79, 80, 84, 168
RC160, 18-21, 168
RC161, 26, 28, 33, 66, 168
RC162, 27, 34, 39, 40, 44, 169
RC163, 46, 59, 66, 169
RC164, 66, 73, 169
RC165, 73, 74, 80, 169
RC166, 23, 80, 81, 84, 88, 89, 90,
169
RC166N, 89, 170
RC170, 46, 170
RC171, 46, 47, 170
RC172, 66, 74, 170
RC173, 84, 170
RC174, 23, 87, 89, 170
RC180, 66, 170
RC181, 23, 84, 85, 90, 91, 94, 95,
102-104, 106, 141, 171
RC181N, 89, 90, 171
Redman, J., 7, 24, 25, 32, 37, 41,
60-63, 67-69, 75-78, 97-106
Rennfox, 153
Rennmax, 17, 153
Reynolds, 102-104, 106, 130
Rigal, 132
Robb, T., 41-43, 60, 62, 100, 119
Romero, G., 119
Rougerie, M., 119
RS1000, 136, 138, 139, 173
RSC, 96, 107, 109, 112, 113, 115
RSC350, 107Ruiz, R., 123, 132,
139
Rutter, T., 128
Samin, E., 136, 137, 139
Sarron, C., 131, 138, 139
Sato, Y., 98
Savage, S., 116
Schneider, 128, 133
Schwemmer, E., 128, 131, 133
Shepherd, A., 63
Shimazaki, S., 32, 98
Showa, 106, 147
Sidecar, 59
Silverstone, 145, 147, 151
Simson, 17
Singapore, 20
SMAC, 126
Smith, B., 119
Smiths, 23, 102
Solitude, 24, 98
Soulas, P., 128
Spain, 32, 67, 68
Spencer, F., 151
Spierings, L., 128
Sprayson, K., 102
Stinglhammer, 128
Struyk, B., 136
Sumiya, M., 112, 115, 121
Surtees, J., 103, 104
Suzuka, 43, 69, 75, 100, 105, 132,
136, 139, 140, 150, 151
Suzuki, 41, 60-62, 67, 68, 75, 86,
96, 119, 122, 132, 136, 137, 139
Suzuki, G., 97
Suzuki, J., 97
Sweden, 32
Takahashi, K., 32, 41, 60, 62, 98,
100, 103
Tanaka, T., 32, 41, 97, 99
Taniguchi, N., 16, 32, 97, 98
Taveri, L., 25, 32, 37, 41, 43, 60-62,
67, 68, 75, 97, 99, 102
Thruxton, 123, 128
Tost, 136, 139
Triumph, 119
Turbo, 152
Tuxworth, 128
Ubbiali, C., 24, 25
Ulster, 25, 32, 47, 60, 68, 76, 77, 98
Urdich, D., 119
Vial, 128
V-twin, 152
Wal, J. v.d., 133, 136, 139
White, 128
Williams, C., 122, 123, 128, 131,
132
Williams, R., 147
Willoughby, V., 141
Woodman, D., 68
Woods, S., 122, 123, 128, 131, 132
Yamaha, 60, 62, 63, 67-69, 75, 76,
86, 87, 96, 98, 102, 103, 119, 122,
131-133
Zandvoort, 122, 128, 131