As mentioned on the
“Preperation” page, the Yamaha R1 engine was selected for its good bang for
your buck. I managed to get hold of a 2003 spec injection engine. The injection
system gives a little more power than its carb old brother, and a broader
power band.
It is an impressive
package, its just so small and light:
I can pick
it up on my own
This was left with
Zcars and came back all set up in the frame, as you can see from the photo:
Engine in
frame, with all rear drivetrain, waiting to be fitted
We had fun and games
fitting the frame into the body shell. You don’t want to cut too much metal
off but its a tight fit. It was a case of lifting the body over the frame...does
it fit? No! cut a bit off here and there and try again. Once in, its a simple
job of bolting the front part of the roll cage to it, making sure its all
square and bolting it to the shell.
Cooling
Was took a little
thinking about, the Yamaha radiator has a lot of connections, mine has the
basi in and out. The diagram below shows how I plumbed it
Engine
plumbing diagram
Which ever way its
done it uses a lot of hose and the system has a pretty large water capacity.
Don’t under estimate what a difference boxing the engine in behind the
bulkhead makes. Without the bulkhead and rear wndows the system would
regulate it self at 80oC just on switch of the thermostat.
Once it was all boxed in behind the bulkhead it needed the fan t oswitch in
and out. This was a little un-nerving as that doesn’t happen until 99 oC!
A little hotter than I’m used to seeing on cars. Once the fan switches it, it
quickly drops to 92 oC.
Fueling
Check out the
seperate fueling section.
Throttle
The throttle linkage
was a tricky one to get right. Obviously the linage is long, Zcars supply an
8foot long cable. But getting this cable to have a smooth action is tricky.
The original instructions are to drill the throttle linkage to move the pull
point on the shaft lower, reducing the amount of cable pull. Then run the
cable into the front engine bay, down the transmission tunnel and up to the
throttle bodies. This requires a 180degree tight turn in the cable at the
pedal end, resulting in a lot of drag. Now Zcars have a lever that bolts on
to the front sub frame. A short cable goes from the pedal to this lever and
the other end to the 8 foot cable, so this turns the motion through
180degrees. This works well, once some extra return springs have been added
to the new lever.
Another throttle
linkage problem is at the throttle body end. The end to the cable can flop
about on top of the cable stop. Adding a support to this and using the lock
nuts to bolt the cable to the stop makes for a better throttle action. With
too much slop there, the throttle sometimes wouldn’t shut fully..
Clutch
The clutch setup of
the zcars/R1is to use the original mini master cylinder up front, original
slave cylinder at the transmission end then modify the cable pull clutch
actuator to a push rod by welding some M6 stud to it. My first problem was
that the zcars positioning of the chassis tab to bolt the slave cylinder is
at the wrong angle. It points the cylinder to the wrong side of the pivot
point meaning that at full extension the push rod is at a silly angle. I
solved this problem by shimming the slave cylinder out to the correct
angle. The next job was to make an
adjuster. I bought some 8mm steel rod that just nicely slipped over the M6
stud and with a nut on the stud as an adjuster it was sorted.
Next I ran into
trouble! I had made the adjuster too short, I stood on the clutch and popped
the end out of the slave cylinder. I stripped it down and decided it wasn’t
worth repairing. The bore was scored and the seal damaged, as replacements
were only £20 for the complete cylinder I just ordered a new one.
With a new slave
fitted and a correctly sized adjuster I tried the clutch. It wasn’t
clearing...bugger. It had worked before. I had read on some web page or other
R1 clutches can stick if they had been over pushed...it was time to take the
cover off and look at the problem. I found bike clutches are very easy to
strip and rebuild, the problem, I think, was lack of use. A bike clutch is a
wet clutch, but with the engine being stood for so long the clutch was dry
and had stuck shut. I gently released the plates, bolted it back together and
hey presto, the clutch worked. I adjusted the clutch so that bottoming out
the pedal didn’t take the actuator beyond its limit or the slave cylinder
beyond its max.
Exhaust
The system came with
the kit, so didn’t need a lot of work. The ting that needed thinking about
was heat management. The headers come down the front, close to the bulkhead
so the headers need lagging in exhaust wrap. A bargain from E-bay got me 100
foot of wrap for £20, compared to Deem Tweeks at £1 per foot, as was very happy! I lagged the system right down to where it
disappears in he 4 to1 collector under the sump. I also lagged the
accelerator cable with it along with some reflective heat shield. The
handbrake cable and electrical cabling anywhere close to the exhaust also
came in for some lagging.
I fitted the
silencer when the car was on axle stands. On fitting I thought it might be a
bit short on ground clearance. On dropping the car on its wheels I found the
clearance to be all off 5mm (memories of the Tiger’s grounding sump came
flooding back to me). I’d noticed the Zcars demonstrator had a cut out in the
rear valance to allow the exhaust to be raised, so I chopped a semi-circle in
mine to get a couple of inches clearance. There’s stacks of room, so an oval
exhaust can would buy another inch, or an exhaust across the rear valance
would be better...all options for the future.