The Knowledge - Velocette Owners Club

and pinned and the preload set up correctly, i.e. zero clearance at working temperature. the use of a
slave outer bearing is invaluable for doing this, as you don’t have to keep trying to get the outer bearing
out as a normal interference fit. dodkins used this method, and if you think it through, it is the most
sensible and logical approach. if I bought another velocette the first thing I would do is to have this mod
done. if I bought a thruxton and because of their very high prices, I would fit a modified crankcase half
supplied by nick payton and use the bike with that fitted. the price is so cheap, its almost a joke.
tremendous value for money. the original half could always be put back on the motor, if ever there was
a time to sell it. going back to the taper bearing set up, one outer race is the same as another. a
machine does not spit them out at different sizes, cnc programmed machines just don’t that.
L #2654 What's best to use for sealing the crankcase halves? Don't want any crazy colours!
Unfortunately the motor wasn't sealed properly and it's leaking from the inside into one of the back
mounting lug holes and coming out at either end, took me ages to trace it!
#2656 Two products are in my quiver. If the mating surfaces are in excellent condition and I have no
reason to suspect a problem, I use Hylomar Aero Grade. If the surfaces are otherwise, I use Three
Bond 1014. Depending on your location in the world, Honda Bond or Yama Bond may be more readily
available and are comparable in quality and characteristics.
L #2862 When I dismantled my engine for a re-build on the main shaft up against the main
bearing and behind the front sprocket somebody had put an eighth washer. This you could see had
been done to stop the primary chain from rubbing the case behind you could see where it had taken
chunks out before. with regard to this mod the engine worked fine and the clutch worked fine. with the
washer in place the two sprockets were in line but remove the washer and the primary chain starts
taking chunks out of the crank cases and primary chain case
#2865 Veloce seemed to have various offsets for the front sprocket, on a selection I have they vary by
anything up to .060". Dependant upon which front sprocket I have on my Venom racer, I also use a
washer .100" thick to provide correct chain alignment and also ensure that the inner face of the
sprocket clears the main bearing boss. Obviously the thickness of washer (if necessary) can vary
according to the shimming behind the main bearing outer race and the relative position of the crank
within the cases. As you say, the washer helps to line them up correctly in your engine and it works
satisfactorily. I only replied to make you feel better and to let you know that you are not alone!
#2870 After running my VM for over 10, 000 miles with obviously misaligned sprockets ( you should see
the scuffing on the outboard side of my clutch chainwheel!), I eventually got them to line up by making
a spacer out of an old main bearing inner race ground to about 0.10" thick. Before you shoot: yes, I've
got the chainwheel in the right way round and there are no weird spacers behind the engine/gearbox
mounting plates. The gearbox final drive ball race is fully home in its housing (except it's not truly the
final drive bearing on a Velo, of course) and the gearbox is a standard Prefix 12. Everything works fine
but my primary chaincase "pants" or, if you prefer, "oilcans" when I pull in the clutch and this would
explain why my downshifts are a bit rough. So what is causing the complete clutch assembly to be
offset towards the primary chaincase outer cover by what appears to be one tenth of an inch? I do not
accept that this could be the result of cumulative wear on the original Veloce jigs.
#2871 Seems to me that you would cure both the misalignment and the flexing of the case by reducing
the length of the spacer behind the backplate of the clutch, no?
L #3709 I am in the process of rebuilding my 53 MAC engine. However I am finding it very difficult
to set up the end float. The book says there should be no more than 0.0015in of movement. However
the best I have managed is 0.002 at BDC and very slightly tight at TDC. Is this likely to cause a
problem? I cant understand why the end float should vary with crankshaft position?
#3711 Difficult to diagnose at a distance, but I think I'd strip the engine and check the complete flywheel
assembly for truth.
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