go club racing from scratch, with a carisma m40s

Carisma RTR Electric 1/10th 4WD Touring Car
By stephen bass
Who’s for
Clubbing?
Go Club Racing from Scratch, with a Carisma M40S
SPOILT FOR CHOICE
Considering that I live in a fairly rural part of the UK, I think I am very
lucky in that for many years, there has been a very healthy club racing
scene in the region. In fact, within a 30-minute drive of my home I
have a choice of no less than seven clubs offering weekday evening
winter indoor club racing, on a choice of carpet or polished wood track
surfaces. What’s more, if I were to allow an extra 15 minutes travelling
time, my choice would extend to ten venue options, with a choice of
either carpet or wood, every night of the week!
That is all well and good, but everything in my ‘R/C garage’ is nitro
powered, and in any case, I usually confine my race day activities to
assisting my son on the spanners or in the pit lane. So, in an effort
to help throw some light on getting into the club racing scene, I was
16 WWW.RADIORACECAR.COM 03/10
tasked with sourcing a suitable car and having a bash at club racing;
here’s my story as a touring car novice, and the lessons learnt along
the way.
SETTING THE SCENE
I checked out the BRCA website www.brca.org and had a chat with my
local hobby shop, to find out which nights my local clubs race. I don’t
know which club I want to join yet, so choosing a car I can race on a
variety of surfaces would be good. Cost was going to be an important
factor because I needed to buy quite a few things to get started.
All of these things pointed to an electric powered RTR 4WD model
being the obvious choice for me, as this represented good value for
money and gives me all the essential ingredients. I chose the 1/10th
rrci feature
Main Pic: Note attention to detail,
winglets front and rear, front splitter,
door mirrors, rear wing
Carisma ‘Vodaphone’ Mercedes C Class DTM car, as this gave me a
complete RTR package, including all the radio gear, batteries and a
mains charger. It could easily have been a different make or scale of
car, but after a trip to the nearest club, I thought it looked a popular
choice, and the kit motor already complied with their rules.
Whilst this was enough basic equipment to get started, I was clearly
going to have to get a few other bits and pieces. But first let’s take a
closer look at the Carisma M40S, and see exactly what we got for our
money.
UNDER THE SKIN
The bodyshell is beautifully finished in the primary sponsor’s livery,
with a high level of realistic detail including a removable front splitter,
front and rear winglets and that biplane main rear wing. It is actually
modelled on the 2002 DTM C Class car of Bernd Schneider’s, the most
successful driver in DTM history, who hung up his helmet after the
2008 season at the age of 44.
The factory applied decals were all perfectly applied and positioned
on the bodyshell, which is retained by four ‘R’ clips which are actually
handed. Attention to detail or what! The width of the car is 185 mm but
it can be adjusted to 190 mm, making it compatible with a huge range
of optional 1/10th shells.
JUMP IN THE TUB
A plastic tub features a central shaft drive to the front and rear
geared differentials, above which is a central reinforcing upper
chassis deck. I was slightly disappointed to see that there is no foam
protection to the plastic front bumper, so my first job was to fabricate
a bumper from a sheet of foam. When I got the shape I wanted I simply
drilled a couple of holes to allow it to slide over the front body posts.
To hold it in place I slid a couple of old wing mount buttons down the
body posts and retained each side using a body clip through the lowest
hole in each post. Simple! Now I don’t have to worry too much about
damaging that pretty bodyshell when the scenery jumps out at me.
03/10 WWW.RADIORACECAR.COM 17
Carisma RTR Electric 1/10th 4WD Touring Car
Above: Front end layout with large plastic bumper
From front to rear, the right-hand side features an MS-103 steering
servo. On top of this sits the MRX 04 receiver and its front mounted
ON/OFF switch, alongside the MSC-04RB forward/reverse electronic
speed controller (ESC), and the 19 turn brushed motor. The pinion and
spur gears are both 0.6 module, and I was pretty sure the 20T pinion
meant it’s going to be over geared for the first venue I was going to
race at, so I made a note to look into this before I got to race it for real.
The left-hand side of the chassis is cut away to ventilate the 6-cell
NiMH battery pack, which is restrained by ‘R’ clips and it can be
inverted to suit a LiPo or stick pack. The kit comes with a 1400 mAh
NiMH 7.2 V stick pack (and slow charger), but I will need to buy another
three packs if I am to cope with the quick-fire format of three heats
plus final on a typical club night. I will also need a fast charger, as it
is impractical to consider charging all four packs using a wall charger
with an output of just 0.4 Amps. Even a moderately priced charger will
comfortably do the job about nine times quicker.
A couple more items on my ‘To Do’ list include removing the two
power sapping bullet connectors on the motor wires, and to solder
the wires from the ESC direct to the motor. If you are careful, this can
be done using the existing wires from the ESC, as they are just long
enough. The other performance modification that I shall make is to
remove the Tamiya type battery plugs and replace these with a more
efficient connector.
POWER PLAY
The transmission is a fairly simple design featuring a spur driven
central propshaft. There was about 2 mm of play at the end of the
shaft dog bone, but rather than shim this further, I decided to leave
it as there needs to be some movement there to compensate for any
flex in the chassis. The propshaft is plastic, and not what you might
describe as being straight! Later running confirmed that whilst this
18 WWW.RADIORACECAR.COM 03/10
Above: Chassis underside is well vented for
motor and cells
Above: Stick pack batteries (and slow charger) included in the
RTR kit is enough to get you going!
didn’t cause any problems in itself, the resulting vibrations from the
out of balance shaft must have an adverse effect on efficiency and
performance. The shaft drives the front and rear geared differentials,
with steel dog bone driveshafts transmitting the power to all four
wheels. The wheels are attached using a standard 12 mm hex hub and 4
mm centre locknut. The multi-spoke wheels are fitted with 24 mm wide
moulded rubber slicks with foam inserts.
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Above: 19T motor was ideal for
indoor racing. Just the right amount
of power without overheating thanks
to vented chassis
The simplicity of design is continued with
the suspension geometry, but you do get
two upper and lower mounting points for
the front and rear shocks. The front upper
camber link offers two inboard roll centre
mounting points, whilst the rear camber
links have no less than three inboard
and outboard mounts. You do not get
adjustable turnbuckles with the M40S, but
front toe and camber are adjustable via
the threaded link arms. It’s the same story
at the rear where you can adjust camber,
but not toe. Droop adjustment screws are located in each of the lower
wishbones and ride height adjustment can be changed by swapping
shock spring preload spacers, although no spacers or spares are
included with the basic kit. We aren’t told about the standard spring
rates or what shock oil has been installed by the factory, and whilst I
think I will have to go softer and lighter for the low grip polished wood
surfaces, for other surfaces I’m going to try the standard settings first.
Accessing the lower motor adjustment screw is a bit of a challenge,
so I swapped both of the standard crosshead screws with pan head hex
screws and washers so I could use a 2.5 mm ball-ended Allen driver.
There is an inspection hole in the chassis top deck to access the motor
pinion set screw. If you open up the hole a little (working towards the
centre of the chassis), it will make swapping pinions a little easier
as you won’t then be working at that slightly awkward angle. It is, of
course, very important to set the gear mesh between the motor pinion
and spur gear, for the smallest amount of backlash. Mesh the gears
too tight and you could overheat the motor and possibly damage the
electronics, but too loose and you risk stripping the spur gear. Rotate
the spur fully through one revolution, repeatedly checking for that
telltale ‘tick’ to ensure there are no tight or loose points.
Below: Always a good idea to mark and ID your wheels before
the first run
Above: ‘Bot dots’
are included for
driver training
and practice,
perfect if you
don’t have a
proper track
near you!
Right: Also in
the box… 27
MHz radio,
battery and slow
charger, plus
radio batteries,
it’s plug and
play
Apart from that
the Carisma is very
easy to work on. If you don’t already have some basic tools, I suggest
you buy a good quality cross head ‘Posidrive’ No 1, and a 3 mm Philips
screwdriver. Those, and a pair of long nose pliers will achieve 99% of
all maintenance, as you get a motor pinion Allen key and wheel nut box
spanner in with the kit.
Stock brushed motors are equipped with notoriously hard brushes
that take a long time to fully bed in on the motor’s commutator, but it’s
then just a case of applying ‘comm drops’ to the motor and running the
motor directly off a 4-cell battery pack for a few minutes. I flushed the
motor out with motor cleaner spray, and repeated the process three or
four times until I could see that the brushes were sitting much better
on the commutator, and the motor was going to deliver so much more
power and revs thanks to the brush surfaces being able to pass current
into the motor more efficiently.
PRACTICE TIME
One of the surprise items that came with my Carisma RTR package
was a set of yellow plastic ‘bot dots’, shallow domed circular corner
markers, which can be strategically positioned in a safe open area to
help beginners learn all about throttle, braking and steering control.
However, before all that I slotted in a freshly charged battery and
03/10 WWW.RADIORACECAR.COM 19
Carisma RTR Electric 1/10th 4WD Touring Car
Above: Standard hex hubs adapt to all popular 1/10 touring car
wheels
Above: We changed the Tamiya plug for something better and
removed the bullet connectors, before soldering the motor wires
direct...
checked that all the radio settings were good. The manual explains the
simple process of the LED assisted one-touch ESC set-up, so after a
quick check on the steering trim and EPA and I’m ready to go. Before
I actually get to race the M40S I will fully check all suspension and
steering geometry, but for now the kit settings look fine. So I headed
for an unused tarmac car park in a nearby village and set out my
imaginary track. I positioned the bot dots so that I would have two
heavy braking areas and sharp turns, a chicane and a fast sweeping
curve linking my two hairpins.
An enjoyable session saw me get acquainted with the car, then I
headed back home and set about preparing for my first ‘proper’ outing
with the Carisma in just a few days’ time at the East Shrewsbury Buggy
Racing Club in the small village of Rodington. This was where my son
had his very first race meeting some 18 years ago, and where the race
format is very much the same today as it was all those years ago.
FINAL PREPARATION
You can just go and race the M40S straight out of the box. However,
there are a number of things that are worth checking first. Here then,
are a few tips that you may want to consider checking out before
heading off to the track. They aren’t expensive, but they will help to
keep your car on the track as opposed to being in the pits, and they will
also help to make it better to drive and maybe a little quicker.
As I mentioned earlier, with three quick-fire heats and a final,
the single battery supplied with the car wasn’t going to be enough.
Remember, I am a rookie on a budget, so I don’t need anything too
fancy, and £50-£60 should be enough to cover my extra three battery
packs and an inexpensive charger. I decided to go for a Prolux charger
that will operate from both a mains supply or a 12 V leisure battery.
Mains power is available at all my local clubs, so I don’t need to worry
about the added expense of a 12 V leisure battery just yet.
My practice session revealed that the car had very free-running
differentials, and they were also a little noisy. So my next job was to fill
both diff cases with grease, using slightly thicker grease in the front diff
than the rear. This would quieten the transmission down, and make the
car less likely to swap ends when turning into tight corners (of which
there are many at Rodington), and make the car drive better out of
the corners. Accessing either differential is quick and easy, by simply
removing the three upward facing screws holding the shock tower on,
followed by the six screws holding the upper diff casing in place, and
the top cover can be lifted off and the diff removed. What’s more, all
nine screws are exactly the same, so you don’t have to worry about
‘what goes where,’ nor do you need to worry about diff orientation,
as they will only fit in the bulkheads one way! I used the 3 mm Phillips
screwdriver to remove the three small countersunk screws to ‘split’
each diff, which revealed only the lightest covering of grease on the
gears. I would suggest adding proper grease is a worthwhile exercise,
as you will enjoy the double benefit of improved performance and
longer life from your transmission.
20 WWW.RADIORACECAR.COM 03/10
Above: ...The result is neater and more efficient
Lastly, it’s a good idea to apply some lubricant where the bevel
gear and centre shaft pinions mesh. Although these are enclosed, it’s
best to use a lubricant that will stay on the gears and not fly off the
first time you switch on. I use Holts Spray Grease (www.holtsauto.
com) for this, or if you prefer less mess, try Rock Oil Chain Wax (www.
rockoil.co.uk) which are equally effective and available from most car
accessory outlets like Halfords, but allow it to dry before spinning the
transmission under power for the first time.
Another tip which I have mentioned in previous features that can
potentially make your transmission last twice as long, is to swap
driveshafts around after each rebuild so they share the wear on
both sides of the dog bones, diff out-drives and the axle drive cups,
extending the life of all these parts.
All that remains is to sort out the gearing. If I was really starting from
scratch, I would probably buy a few extra 0.6 module pinions to give
myself some gearing options, but as I already have a set of 48 DP
pinion gears in my son’s pit box, ranging from 14 to 30 teeth it would
solve all my problems if I could just swap the spur gear to match. I
found that the Robinson Racing (RRP-1875) 75-tooth 48 DP spur is a
direct swap, so with that fitted, I went for a 19-tooth pinion which gave
me a slightly lower drive ratio of 3.9:1 from the kit standard 3.6:1.
ALMOST READY
I found that most of the battery packs I would be using in the Carisma
required some packing to stop them from floating around in the
battery tray, but because they all needed differing amounts, I decided
to use strips of servo tape to do the job, rather than just adding some
padding on the chassis.
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Above: Working on the M40S is easy, with good
access to most components...
Above: ...Although the lower motor
screw is difficult to reach so we
changed ours later
Above: Servo and servo saver horn.
Note the mounting plate above for
the radio receiver
Next I made a note of the
frequency crystals, but there was only
standard camber and toe
one heat in my class on that night
settings, and gave the car a
and most drivers were on 2.4 GHz,
final trial run to re-check all
which doesn’t require interchangeable
the radio parameters. It was
frequency crystals.
at this point that I discovered
After this, I lent a hand to the folk
quite a lot of free play in
building the track, rolling out and taping
the driveshafts. None are
down the carpet. As more people arrived
shimmed, and checking the
there was a huge range of models being
manual confirmed that only the
unpacked in the pitting area. 1/10 and
centre driveshaft is actually
1/14 touring cars, F1 cars, 1/12 scale,
shimmed with ‘O’ rings. So I
stock cars and 1/18 scale buggies and a
dismantled each corner of the
truck or two.
car and fitted a small section
A heat sheet was printed and I noted
of fuel tubing (shock ‘O’ rings
my heat and race number, as the latter
work just as well) into each
item also related to my transponder
outdrive, using a dab of diff
number. Before I knew it, it’s my first
grease to hold them in place
heat, so I placed my car at the back
during re-assembly. A final run
of the field and let everyone else get
confirmed a much smoother
away before I tentatively made my way
running transmission at the
around the track. As I crossed the loop
full extent of suspension travel
for the first time I heard a confirmation
and steering lock, and I am less
‘beep’ as my transponder recorded the
likely to have a driveshaft pop
start of my qualifying run. I was just
out during a race.
concentrating on getting around and
The club runs hand-out
staying on the track, but it seemed like
transponders for lap counting,
in no time at all I was being caught and
so I made a small Lexan
lapped so I tried to just go wide on the
mounting bracket which would
next corner without loosing too much
retain it with another, larger,
speed to let the quick guys through.
Above: Removing either diff is a quick and simple process
body clip. This will suffice but
For the second round of qualifying
that could only be rebuilt the right way round! If only they
a personal transponder (PT) is
I thought I would try a set of RP30
were all this easy!
most definitely on my wish list.
moulded slicks from Take Off. These
Although I can race as a ‘guest’ at my first meeting, I have already
come as a pre-glued set (RP30BGL) mounted on white-dished wheels
sent off my membership application for my 2010 BRCA licence. Many
and are a BRCA approved race tyre. With some Jack the Gripper
R/C car racing clubs are affiliated to the BRCA and it is a condition of
additive across the whole width of the rear tyres and the inner half of
entry that you must be a member. I won’t go into the many benefits
the fronts, the improvement was immediately noticeable, and even at
of BRCA membership just now, but you can get all your questions
my pedestrian race pace I could feel the grip coming up after about
answered by visiting their website at www.brca.org This is also an
four laps as they got some heat into them. A word of warning here
excellent place to find out where your local clubs are and to learn
though, do check with your club first to see if they allow tyre additives,
about the rules of racing whatever class or scale you choose.
and if they do, also ensure you know which type/s they allow before
parting with your cash.
RACE DAY 1
After three runs I found that I was enjoying myself more and being
After charging my battery packs at home and fitting fresh cells in
intimidated less by the quicker drivers. I was also going a little quicker
the transmitter, I headed off for my first meeting. On arrival I grabbed
now, and even starting to think about how I could make the car handle
a table and set-up my gear in the pitting area. I then booked myself
better! I ended up in a totally predictable last place on the grid for my
into the meeting with the race director who needed to know my name,
final, and that’s where I finished. However, I didn’t care, I had finished,
my radio frequency, and the class I was racing. This data, plus my
and I had enjoyed myself. What’s more, I hadn’t ruined anyone’s
BRCA number and a rating of my ability (usually on a scale of 1-10)
evening with my rookie driving errors, which I must confess was my
was entered into his archive file within the race control software. At
primary concern when I first arrived, and the Carisma was still in one
a bigger meeting I would be expected to have at least three sets of
piece!
03/10 WWW.RADIORACECAR.COM 21
Carisma RTR Electric 1/10th 4WD Touring Car
Above: Ball raced gear diff and metal dog
bone driveshaft
Above: Factory diff grease is adequate but
minimal. We later added plenty of much
thicker grease for improved lubrication and
better ‘action’
RACE DAY 2
My next outing would be on a very low
traction polished wood track, so I was in
for a bit of guesswork so far as set-up was
concerned. I was happy with the balance
and traction of the Carisma on the carpet
at Rodington, so I left the differentials as
they were. However, I certainly needed to
refill the shocks with thinner oil and fit some
appropriate tyres.
I dug out one of my son’s old set-up sheets
for his touring car, and found that he ran 10
weight shock oil front and back, so that’s what
I went for. Although the next track was longer
than at Rodington, it was more a case of it
having a longer lap than being a faster track,
so for now, I was content with just a shock
oil and tyre change, leaving the gearing as it
was. I also moved the shocks so that they were
standing up more on their outer mountings.
When I visited my local hobby store I bought
a pair of hard and soft comm cleaning sticks,
enabling me to give the motor a quick service
before its next outing. I also bought a set of
wheels and some soft compound mini pin tyres
and inserts that I know would work on polished
wood. A trial fit of these at home proved that I
had to remove a tiny amount of the bodywork
around the rear wheel arches, as they are a
higher profile than the moulded tyres that I
had run so far.
So, with that done and the car loaded up
again, I set off for my second meeting, this
time in a sports hall at Madeley, the home of
the Telford Hot Trax Club. The polished wooden
floor felt like racing in the wet on slicks, and
called for a very delicate touch on the throttle.
The slightest brush against the track markings
or contact with another car would send me
spinning or sliding off with little chance of
recovery! All the same, it was such great fun,
and made the job of understanding what the
car was doing a lot easier than when I ran it on
carpet. Here I played around with the throttle
and steering and learnt the best way to get
it to turn into a corner, and, having achieved
that, I experimented with lines and throttle
application coming out of corners. To anyone
watching this, they probably just thought that
I didn’t have a clue what I was doing, and that
the car was all over the place, or maybe that
I should take up drifting! But no, I promise, I
was trying to learn as much as possible about
the car and the track, in what little time I
had. To my surprise however, the thing that I
struggled with the most was getting the car up
to a respectable speed on the straights. The
Above: For racing we fitted some sticky
RP30 moulded slicks which gave a noticeable
improvement on carpet and tarmac
Above: As I only have 48 pitch pinions in my
pit box, I swapped the kit 0.6 module spur
gear (right) for a white 75T ‘Robinson Racing’
48DP equivalent
Above: Sliding around a downhill left on the
tarmac test
22 WWW.RADIORACECAR.COM 03/10
Above: Main spur and rear diff
pinion assembly is also ball raced.
Centre driveshaft dog bones locate
in drive cup at front and rear
combination of too much power too soon,
and over-correcting the steering got me
into many non-recoverable tank slapping
moments! Hmm, maybe that rear diff
could do with being a bit looser after all.
However, when I did get that bit right,
it was almost invariably followed by
getting my entry speed and line wrong at
the next corner, with chronic understeer
or completely backwards! I thoroughly
enjoyed the evening and came away
feeling that I had learned more about the
car, and I had some ideas about set-up
changes to suit racing on polished wood.
Isn’t that how it goes for all of us in this
sport, and what makes us strive to do
better all the time?
TARMAC TEST
After my two club races I visited a local
on road track to shake down the Carisma
in a private test session. My busy schedule
prevented me from racing the Carisma
on tarmac in the time allowed, but I fully
intend to do so during the 2010 season.
On the day of the test it was dry, but
the track was still damp and greasy from
overnight rain, and it clearly wasn’t going
to dry out during what was a typical
gloomy winter’s day. I decided to run the
car on the kit tyres and also the RP30’s,
both of which had performed well on
carpet. Perhaps it was the slightly harder
compound of the kit tyres, but I found
they were giving slightly more grip in the
slippery conditions. I was still running the
lightly damped set-up that I had used
on polished wood, and it worked really
well! The test was proving to be great
fun, power sliding the Carisma around the
greasy track, but if the truth be told, it
wasn’t teaching me a whole lot about how
it would work in the dry! And as to gearing,
I hadn’t got a clue because I was spinning
the wheels wildly. So the dry tarmac
learning curve will have to be climbed
another day.
So that concluded a very hectic week
from first unpacking the car to practising,
tearing it apart, making modifications,
racing it a couple of times and finally a
thrash test on tarmac. My next outing
will once again be on polished wood, but
this time at the Ludlow Radio Car Club’s
school hall venue, and I can’t wait!
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Above: Getting defensive. Keeping a tight line on the high traction carpet
QUICK SPEC
Class: 1/10th 4WD Touring Car
Type: RTR Electric
Manufacturer: Carisma
Price: £122.49 RRP
WHAT YOU GET
Pre-painted bodyshell
19T brushed motor
27 MHz radio Tx and Rx
Forward/reverse ESC
1400 mAh NiMH battery
8 AA Tx batteries
5 Plastic ‘bot dots’
400 mA 230 V mains charger
Box spanner
Motor pinion key
WHAT YOU NEED
CONCLUSION
The Carisma M40S is an amazing value for money package that fulfils its purpose superbly. It
provides the novice driver with affordable, no-nonsense machinery that is good enough to stand
up to the rigours of club racing, while you develop your driving skills. It’s cheap to buy, fun and
easy to drive, and you wont need a second mortgage to finance maintenance or repairs. The 4WD
transmission makes for less demanding driving and gives you the chance to race on a multitude of
surfaces. I shall continue to race indoors through the winter, but I fully intend to race it on tarmac
once in a while during the summer, and there’s even talk of a Carisma on road event taking place mid
2010, so watch out for details of that.
There isn’t a huge range of hop-ups waiting to tempt you to spend more money because that isn’t
what it’s about. You can go out there and pay four times the price (or more) for your first car, but the
net result is that you will probably just be hitting the scenery harder and hurting your wallet! Accept it
for what it is, and the Carisma makes perfect sense. So... do you get it? You should! RRCi
No 1 Posidrive
3 mm Philips
Long nosed pliers
disLikes
No foam front bumper
Plastic propshaft
Tricky access to motor screws
No turnbuckles
Likes
Fantastic value for money
A truly complete RTR package
Perfect starter car
Enough ‘adjustability’
Looks great
More than adequate performance
Easy to maintain
Great after sales support
CONTACT
For more information
contact CML Distribution
Telephone 01527 575349
or visit www.cmldistribution.co.uk
03/10 WWW.RADIORACECAR.COM 23