FJR1300 CYLINDER HEAD OVERHAUL WITH CUSTOM VALVE GUIDES My purpose

Transcription

FJR1300 Cylinder Head overhaul with custom valve guides
FJR1300 CYLINDER HEAD OVERHAUL WITH CUSTOM VALVE GUIDES
My purpose in writing this is to share what I learned doing this overhaul on my own
bike and hopefully provide some tips and gotcha’s to be avoided. It is not my intent to
give a step-by-step guide. That has already been done in the Yamaha Service Manual
and this project should not be attempted until you are very familiar with chapters 3 and
5 in particular.
Note:
An excellent reference manual covering head overhaul for any type of car or motorcycle is Sunnen’s
Complete Cylinder Head and Engine Rebuilding Handbook by John. G. Edwards. Of particular interest is the
section on aluminum head to aluminum block multi-layered steel (MLS) head gaskets and torque to yield
head bolts. You can also research these topics on the web.
16 little valve guides is what this is all about.
Custom valve guide is on the left, stock on the right
Disclaimer
All described procedures are for informational purposes only. All modifications and maintenance should be
completed by a qualified mechanic and in accordance with Yamaha factory specification. All information is
provided "as is". No warrantees are expressed or implied. Any work attempted using this information is
done at your own risk and no assumption of responsibility for the accuracy or reliability of this information is
expressed or implied.
All Material © Richard Carroll, 2006. All rights reserved.
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Required tools
Aside from a good assortment of metric tools, you will need the following:
Torque wenches

low range (4-30 newton meters)
medium range (20-200 ft lbs)
Precision measuring tools

Feeler gauge
Dial indicator

Vernier calipers
Plastic gauge
Dial micrometer
Special cylinder head overhaul tools:

valve spring tester
valve spring compressor
Torque angle gauge
History
In April 2006 my 2005 FJR joined the list of ticker casualties. I noticed an occasional loud
ticking at about 12,000 miles and a progressively noisier valve train over time. My
biggest clue was a noticeable loss of power and lower gas mileage (mileage dropped
from 41 to 37 mph).
When the bike reached 14,000 miles I decided to investigate. I removed the exhaust
header pipes and found one exhaust port (E6) much blacker that the rest. A compression
check revealed all cylinders were low but still within spec. Upon removing the valve
cover, a valve clearance check showed all exhaust valve readings out-of-spec. on the
tight side. There was noticeable discoloration of one of the valves (E6). The low limit for
exhaust is .18mm, but all eight valves read .15mm. The intake valves also read .15mm
which is at the low limit of tolerance but within spec, for the intake side. I wondered if
the valve clearance was set too tight at the factory.
The two pictures below show the E6 valve in question:
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Notice the discoloration at the bottom of E6 exhaust valve.
My research
I discussed this issue with my dealer, who said he had never heard of any problems
with the FJR valve train. I then e-mailed another dealer, told him my problems and
mentioned the known issue with the FJR and he said that I was reading too much into
the forum discussions and that 98 percent of all complaints were bogus. As I did not
have the YES warranty and did not want to take all summer to get Yamaha corporate to
react, I decided to fix it myself.
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Since the release of the FJR, Yamaha’s attempt to fix the exhaust valve problem has been
a failure. They have released new versions of the exhaust valve, valve guides and most
recently new valve seals. The record shows that their first two attempts (different valves
and guides) failed. Many factory repaired tickers have exhibited the same valve issues
again (re-tickers) at approximately the same mileage. The newest factory fix just released
in 2006, new valve seals, is yet to be proven. The 2006 model, released in April of this
year has not had enough time or mileage to confirm a fix.
I did research on as many of the old ticker threads as I could find, including all the
Warchild sagas. I concluded that the valve problem is a heat-related issue. A lack of
lubrication might also contribute.
My approach to solve both problems; bronze valve guides for the heat and the new 2006
Yamaha valve seals for more lubrication. Bronze is a much better conductor of heat than
the stock powdered metal. Bronze valve guides are used in most aftermarket high
performance automotive heads (GM Bowtie V8 racing heads) and Kibblewhite Precision
Machining, one of the largest makers of aftermarket motorcycle valves and valve guides
uses only AMPCO 45 (nickel, aluminum, bronze metal) for valve guides, wrist pin and
crankshaft bushings to name a few.
(To learn more about Kibblewhite visit their web site at Blackdiamondvalves.com. To
learn about AMPCO 45 visit Ampcometal.com.)
The teardown
Step 1: Remove the Engine
The first step is to remove the engine. This requires removal of sub-assemblies in the
following order:

Seats and Fuel Tank
Cowlings
Radiator and coolant
Exhaust pipe and muffler
Air filter case
Throttle bodies complete
Air Induction assembly

Thermostat assembly
Engine oil/oil filter
Note
The book says Oil cooler and Water pump, I found this un-necessary
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Left footrest bracket/dust cover
Clutch release cylinder (be sure to tie-rap the piston to keep oil from leaking)

Side stand – complete
Step 2: Disconnect electrical leads as listed in chapter 5-3:

Starter motor lead
Ground lead

Stator assembly coupler
Oil level sensor lead
Sidestand switch coupler

Crankshaft sensor lead

Speed sensor lead
Step 3: Disconnect hoses as listed in chapter 5-3:

Crankcase breather hose
I was then ready to remove the engine mounting bolts and drop the engine. I used a
chain fall centered over and attached to the handlebars of the bike and a furniture dolly
under the engine. I placed wood spacers between the dolly and engine to support the
engine while I removed the mounting bolts. Once all bolts but the rear lower mounting
bolt were removed, I lifted the bike about four inches. Making sure all wiring and hoses
were clear I then removed the last bolt and moved the engine forward to disengage and
clear the drive shaft. Once the engine was free I lifted the bike higher and rolled the
engine clear.
Removing the engine:
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Once the engine was removed I lowered the bike and used the chain fall to lift the
engine onto a steel table for an easier working height. Next I removed the valve cover,
checked the valve clearances for future reference and then removed cam tensioner and
both cams. I removed the valve lifters and pads, they slipped out using a magnet (and
put them in a plastic zip-lock bag marked with their original location (E1-E8, I1-I8).
I then had 16 bags, one for each valve, to hold all valve parts for said location. I knew I
had to reinstall all valve train parts (valve lifter, cotter, upper and lower spring seat,
spring and valve) in their original locations.At this point I could remove the ten head
bolts and two timing chain cover bolts.
Note
The head bolts are very tight; I broke two sockets during the removal. I also had to secure the engine to a
steel post to prevent turning the entire engine when removing the head bolts.
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Cylinder head removed
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Next, using the Valve Spring Compressor tool, I removed all 16 valves and components
and placed parts in the properly marked zip-lock bag used above for the lifters and
pads.
The inspection
After I removed the valve springs, I measured the amount of free play with the valves
installed in the valve guides.
The factory valve-stem-to-valve-guide clearance is:

Intake = .00004 - .0015 in
Exhaust = .001 - .002 in
I measured the clearance with a dial indicator. I zeroed the indicator with valve down,
and then lifted the valve as shown below to read the clearance. I then divided this
number by 3.5 to give a close approximation of stem to guide clearance.
Measuring clearance with dial indicator
This measurement resulted in values as follows:
Exhaust valve-stem-to-valve-guide measurements
Valve
location
E1
Maximum factory spec.
0.002
Measured clearance
0.0077
E2
0.002
0.0086
E3
0.002
0.0057
E4
0.002
0.0034
E5
0.002
0.0083
E6
0.002
0.0071
E7
0.002
0.0029
E8
0.002
0.008
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Intake valve-stem-to-valve-guide measurements
Valve location
I1
Maximum factory
spec.
0.0015
Measured clearance
0.0011
I2
0.0015
0.0014
I3
0.0015
0.0011
I4
0.0015
0.0008
I5
0.0015
0.0011
I6
0.0015
0.0014
I7
0.0015
0.0014
I8
0.0015
0.0011
As you can see all of the exhaust valves was considerably out of spec. In fact, the wear
was so obvious I could feel the looseness in the exhaust valves just by wiggling the
valve.
All the intake valves were within spec.
I also noted during valve inspection that the stock exhaust valves are bi-metal. The
lower half of the valve is SS and the upper half is carbon steel. The SS is more durable to
hot exhaust gases and the steel is more tolerant to mechanical wear from the constant
impact of the cam and lifter. The Yamaha valve is fused in the middle, meaning that the
seam is half way up the stem. This places the fused seam inside the valve guide. (I
question this design, as the heat transferred up the valve stem must cross this fused
boundary.) Also, the seam creates a ridge that can wear on the inside of the guide. This
seam can be felt with your finger nail on the old valves.
A more common approach used by other valve manufactures is a SS valve and stem
with a Stellite tip welded to the top of the stem. The Stellite provides a hard wear surface
over the softer SS metal but eliminates any fused boundary inside the guide area.
Stock Exhaust valve showing SS to carbon steel boundary
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I also noted that the E3 lobe on the exhaust cam had a trace mark on the closed side of
the lobe. This should never touch the valve lifter on the closed cycle unless the clearance
is too tight. The clearance was .3mm out of spec but so were all other exhaust valves. My
conclusion was the lifter was defective (out of round maybe) and not returning to a full
resting position. I replaced this lifter. See below.
Bottom of E3 cam lobe
Top of E3 valve lifter showing wear mark
Other observations during the disassembly; one of the intake valve springs (I2) was
installed upside-down. Didn’t seem to have any negative impact, but did lower my
respect for the factory’s integrity.
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The cleanup
Cleaning the engine block was the next step. This includes cleaning the head gasket
surface area and removing all combustion chamber residues. Take great care when
removing the old gasket material to avoid damaging the highly polished surface of the
engine block.
Before I started, I packed paper towels between the block and the outside of the
cylinders (the water jacket). This prevented crud from going into the water jacket.
Arrows below show water jacket to be stuffed with paper towels or shop rags before
starting.
Engine before cleaning
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Then I used Permatex gasket removal spray, WD-40 and a plastic putty knife. This
worked for all but the most stubborn spots. Only as a last resort did I use a SS wire
brush soaked in WD-40. I used the same tools to clean the top of each piston.
To clean each piston I rotated the crankshaft clockwise until the piston was at the top of
cylinder.
Engine after cleaning
When I inspected the cylinder walls I saw no measurable grove nor could I feel any
ridge in the wall from piston ring wear. This is a good sign that engine is capable of
going several tens of thousands miles without need of a major overhaul.
Noted: erosion, mostly on No.1 piston and some on No. 2.
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Using the same method as with the engine block, I then cleaned the cylinder head gasket
area. I decided not to worry about protecting the combustion chamber or water ports
from crud at this time as the machine shop will do a through cleaning job after new
guides are installed. Again, I was very careful to protect the highly polished gasket
surface area.
A close-up if No. 1 combustion chamber before cleanup
The right machine shop for the job
Finding the right machine shop proved to be challenging. Even though I live in San
Diego, which has numerous shops, I had to do a lot of research to find one that I could
trust.
I believed that because the FJR is a water-cooled, in-line four it would be very similar to
many Japanese four cylinder cars. In general this is true, except that all the machine tools
needed for the FJR head work are much smaller that for an automobile head. The guide
extractors, reamers and hones for the FJR guides are based on 5mm stem diameter.
Most automotive machine shops are not equipped with tools this small. I visited several
motorcycle dealerships and ask their service department who they used for head work. I
then visited each of these shops and questioned their machinist about the kind of bikes
they specialized in and looked over their equipment. Many of the “motorcycle only”
machine shops were one-man operations with very limited equipment. Some even
worked out of their garages. Having no past experience or personal references to go by, I
went with the most reputable and oldest shop in town. They specialized in BMW,
Mercedes, Lexus and Ducati motorcycles and had the best maintained shop of any I
visited. They certainly were not the cheapest but I only want to do this once.
The new parts
After searching in vain for off-the-shelf aftermarket valve components for the FJR, I
called Kibblewhite and talked with one of their engineers, Jerry Ryan. (Kibblewhite is a
machine shop in Pacifica, CA that specializes in valve components for nearly all metric
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bikes. Yes, they have ready made parts for Yamaha; both street and dirt, just not for the
FJR.)
Jerry and I discussed my requirements and I sent him a new stock valve guide and
exhaust valve. I also sent him specifications from the Service Manual. After several
conversations and engineering drawings we agreed on the design. The new guide
would not use a circlip but instead would have a collar machined on the outside of the
guide. This would service the same purpose as the circlip and would add additional
surface area contacting the head for heat dissipation. This collar would be machined so
as not to interfere with the lower spring seat washer.
Custom AMPCO 45 valve guide (left) versus stock powdered metal guide
Custom AMPCO 45 valve guide (right) versus stock powdered metal guide, top view
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In addition to custom valve guides, I opted for custom Black Diamond exhaust valves
from Kibblewhite. As mentioned above,the bi-metal factory valve has the fused seam in
the middle of the stem. This seems like a potential problem area I would prefer to avoid.
The Black Diamond valves are one piece SS with a Stellite tip. The valve is also coated to
improve wear.
Black Diamond valve (left) versus stock exhaust valve on the right. Notice the Stellite tip on
the top of the Black Diamond valve.
The inside diameter of the custom guide is machined under size. This is so the machine
shop will be able to ream the guide to the proper clearances after installation. Jerry
indicated that, depending upon guide-to-head pressed fit, the inside diameter could
change. Reaming and honing after the guide is installed insures the correct valve-guideAll Material © Richard Carroll, 2006. All rights reserved.
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to-valve clearance. Kibblewhite sells hones for 5mm guides. I purchased one but the
machine shop already had the proper size.
The machine work
Once the new guides and valves were available I could deliver the cylinder head along
with the valve parts to the machine shop. Because the machine shop did not want to be
responsible for removing the valve springs or adjusting the valve clearances, I delivered
the head only, with new parts separate.
They then performed the following machine work:

Decarbonized cylinder head
Removed old guides

Installed new guides
Reamed and honed new guides
Resurfaced valve seats
Lapped valves
Resurfaced head (sometimes this is needed. See warning note below.)
When I picked up the head, the valves were inserted in the head and the head was
wrapped in plastic. I had to make sure not to let the valves fall out of their guides as
they are custom fit to the guide and seat as installed by the machine shop. Making sure
that valve E1 stayed in the E1 guide, etc.
Cylinder head after return from the machine shop
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Warning: If the cylinder head is resurfaced…
The FJR cylinder head and block come with a highly polished finish. This is necessary for the multi-layered
steel (MLS) head gasket to maintain a proper seal. Most machine shops will not be able to match this
polished finish if the cylinder head is resurfaced. A typical machine shop head surface finish is measured
within a roughness average (RA) of anywhere from 55 to 110 micro inches or 55 to 110 RA. This finish is
not acceptable for aluminum head to aluminum block with MLS gaskets. A finish of 20 to 30 RA is required.
To obtain this finish, after the machine shop has resurfaced the head, you or the machine shop must further
wet polish the head surface on a surface plate (a very flat surface, usually granite of thick steel) and very
fine sandpaper. The sandpaper will have adhesive on one side to stick to the plate. The service manual calls
for 400 to 600 grit sandpaper. I used 30u. This is a tedious process that can take three or four hours to get
a semi-gloss finish.
If you don’t get the proper finish, the engine will fire up fine after re-assembly but after it has cooled down
overnight and you start it in the morning it will blow antifreeze out the exhaust pipes. This is called a cold
seal problem. Don’t ask me how I know this. The only recourse is to pull the engine and head, polish the
head, buy new head gasket and head bolts (they are a one use only bolt) and re-assemble.
There are only two reasons the head would need resurfacing: head warpage by more that .004 in., or
scratched surface. My cylinder head had none of these issues but because I did not explicitly tell the
machine shop not to resurface the head they did.
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Rebuilding the head
The next step was to re-assemble the cylinder head with all 16 valves, temporarily install
the cams and adjust the valve clearance.
Before re-assembly I checked all valve springs for proper free length with a ruler and
compressed spring force with my valve spring tester. You put the tester and spring in a
vice and compress to 1.3 ins. The tester gauge should read between 30.6 and 35.5 lb. All
valve springs were within specs.
As I re-assembled each valve assembly to it original location I made sure to lubricate all
moving parts with molybdenum lubricant. The service manual calls for molybdenum oil
every place except under the lifter, on the pad and upper spring seat. That is the only
place it calls for molybdenum grease. Molybdenum grease is easy to find, as most
engine assembly grease is just that, but molybdenum oil is more difficult. I did find a
quart of Honda motor oil that contained molybdenum but I doubt if was very
concentrated so I mixed my on blend of molybdenum oil and grease to make a liquid
about the consistency of syrup.
My blend of moly oil and grease
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After all valve assemblies are installed and before the cams were installed, I installed the
old sparkplugs and did a leak test. This consisted of leveling the head with combustion
chambers facing up and filling each of the four chambers with kerosene.
This tests the quality of the valve seat to valve face seal (how good was the lap job). All
the valves on mine leaked a little after ten minutes and showed a noticeable drop in the
liquid level after an hour.
Finally I installed the cams and adjusted all the valve clearances, following the
instructions in the service manual, chapter 3-16. To turn the cams I used a fabric strap
wrench on the cam gear. My biggest challenge was locating the correct Pad sizes. My
dealer didn’t have certain sizes in stock, but the Pads are fairly standard amongst metric
street bikes so I was able to locate what I needed from other bike shops.
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Once all valve clearances are set to specification I removed the cams so that I could
access the head bolt holes prior to installing the head to the block.
Re-installing the cylinder head to block
Before re-installing the head bolts, I made sure that the head bolt threads and holes were
clean. The bolt holes are blind, meaning there is no way for any oil or gasket material
that may have dropped into the bolt holes when I were cleaning the block to escape. I
found some of the bolt holes had considerable oil in the bottom. I used a long stemmed
queue-tip to soak up the oil. I then used a head bolt and made sure it would screw all
the way to the bottom of the threads with no resistance. Once the bolt was all the way to
the bottom, I measured to make sure that was below the depth required by the cylinder
head.
I cleaned both head and block gasket surfaces with alcohol and examined the new
gasket for any imperfections and then proceeded according to the service manual.
Note
The first head gasket I received from the dealer had a blister in the rubber coating. I sent it back.
Once I torqued the head bolts to spec for the second time as the manual says, I tightened
them an additional 180 degrees using the Torque Angle Gauge I purchased earlier.
This is where the head bolts are stretched. A new head bolt is 4.305 in long; the old
stretched head bolt is 4.330 in long. In fact as you tighten this last 180 degrees it will feel
like you have stripped the threads. This is normal, as what you are feeling is the bolt
yielding. I was tempted to tighten this final 180 degrees in stages, 60 degrees all around,
then another 60 all around and a final 60 degrees. Don’t do it. Do the full 180 degrees as
one step.
My final step was to install the cams with the timing chain and crankshaft in proper
orientation. This was somewhat challenging, but following the service manual and the
timing marks on the crank and cams, I got it done.
My last note that deviates from the service manual is when to install the chain tensioner.
Of course you install the cams without the tensioner installed to give the timing chain
enough slack to position the cam gears in relation to the chain. But once you have the
cams installed with all the timing marks aligned, do not turn the crankshaft until after
you install the chain tensioner and released the spring tension. If you do, the chain will
jump a tooth or more on the crankshaft and you timing will be out the window. The
book says to turn the crank several times to insure you timing is correct, then it says to
install the tensioner. That will not work in my experience.
Once all timing was correct, I turned the crank several times, then re-checked the valve
clearances. I found minor changes were needed even though the settings were correct on
the bench. Evidently bolting the head to the block had some effect on the valve
adjustment.
Once the valve and timing covers were installed, I was ready to re-install the engine. I
used the same procedure in reverse to get everything back together. The biggest
challenge facing me now (assuming the head gasket held) was water, fuel and oil leaks. I
had a leaking water hose that connected the thermostat to the radiator. The hose had
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ruptured the inter lining and had to be replaced. Of course it was the most difficult hose
to replace. Murphy’s law.
Expense and Time
My cost for this project is high based on what I know now and how I would approach it
if I were doing it again. I wanted everything new without question. I know now that
several items could have been reused. Part of the problem was I ordered parts before I
disassembled the engine. I did not need new intake valves the original ones showed no
sign of wear. Also, valve cover gaskets were re-usable but I replaced them. I ordered
several parts from my local dealer, and then later I found out about University Motors. I
could have saved at least 25-30% on parts just by using University. Hind sight is 20/20.
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The list below is my cost based on invoice receipts
Part #
5JW-11193-00-00
Description
Gasket, Head cover
Qty
1
Comments
Required
My project
$
13
5JW-11181-00-00
Gasket, Cylinder head
1
Required
$
29
90119-10004-00
Head bolt with washer
10
Required
$
52
93210-18417-00
O-Ring, coolant tube to
head
2
Required
$
3
93210-23787-00
O-Ring, thermostat
1
Required
$
1
5JW-15456-00-00
Gasket, oil pump cover
1
Required
$
3
93210-32172-00
O-Ring, oil pump
inspection
1
Optional
$
3
4FM-14613-00-00
Gasket, exhaust pipe
4
Required
$
22
ACC-Y4020-40-12
Yamalube 20W40 Oil
4
Required
$
16
5JW-13440-00-00
Oil Filter element
1
Required
$
10
33M-12119-09-00
Valve stem seal
16
Required
$
57
5JW-12213-00-00
Gasket, chain tensioner
1
Required
$
1
1AA-12118-00-00
Valve, cotter clips
32
Required
$
38
3LD-12168-??
Valve adjusting pad
16
Required
$
80
RC-051006-G
Kibblewhite valve guides
16
Required
$
297
GPR-051006-001
Kibblewhite exhaust
valves
8
Optional.
$
382
Machine work
Decarbonize Cyl. Head
1
Required
$
27
Machine work
Reface valve seats
16
Required
$
128
Machine work
Install valve guides
16
Required
$
160
Machine work
Hone guides, lap valves
16
Required
$
80
Machine work
Resurface head, only if
needed
1
Optional
$
37
e-bay
Valve spring tester
1
Optional, not required
$
60
Lube
Engine assembly lube
1
Required
$
11
e-bay
Torque angle gauge
1
Required
$
21
e-bay
Valve spring compressor
1
Required
$
50
Miscellaneous Opional parts
91317-06065-00
Bolt, head, chain side
2
Optional
$
4
90201-06016-00
Washer, for bolt above
2
Optional
$
2
CR8E
Spark Plug NGK
4
Optional
$
20
5JW-12111-0000
Intake valve
8
Optional, could re-use
$
89
5JW-14451-0000
Air Cleaner element
1
Optional
$
25
22
3XW-14714-0000
Gasket, muffler
2
Optional, could re-use
$
21
4KG-1111G-0000
Rubber Valve cover bolt gasket
8
Optional
$
27
5EB-12153-2000
Valve lifter, only replace if worn
1
As needed
$
12
Total
$ 1,781
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It took about two weeks to gather all the parts (custom guides and Yamaha parts), two
days to remove the engine, two days to inspect head, one day of cleaning block and
head, four days for machine shop turn around, and two days to assemble, adjust valves
and install head, and three days to re-install engine, adjust and tune. This does not
count a day here or there to find the right size valve pads or get miscellaneous parts. I
ordered the parts May 16th and finished June 12th.
Final impressions
After a five hundred mile shakedown (two rides) close to home, I departed on a three
week, 5,400 mile trip to the east coast. The bike worked flawlessly. Power was back and
so was gas mileage. I checked mileage at every fill-up and recorded a low of 40 to a high
of 49. The low was across the desert (110 Degrees) at high speed (80 MPH +). Mileage
was generally better at higher altitude, in the Rocky Mountains I got 47-49 MPG.
Noticeable impressions after the re-build: The engine valve train noise is much quieter
than I ever remember, even when it was new. Heat on my legs from the engine is cooler,
but I noticed this after I installed the Power Commander. The engine water temperature
indicated on the instrument panel is slightly hotter. The temperature normally runs at
two bars just as before but will more quickly move to three bars if slowing down for
traffic or extreme outside temperature for extended period of time.
My theory is that the new valve guides are conducting more heat into the head than the
stock guides and thus increasing the water temperature. The new guides are 81%
copper, 10% aluminum, 5% nickel and smaller portions of iron and magnesium. Both
copper and aluminum are much better conductors of heat than the powdered metal of
the stock guides.
Only time and mileage will tell if this is the permanent fix. I certainly hope it is as I
really like the FJR. It is the best all around bike I have owned.
Parting shot. Near Bryce Canyon, UT, after the overhaul
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