On my rebuild the cush drive parts don't seem compatible .
The 4 lobe bearing sleeve which slides onto the crankshaft, part No =65-2523 (i think ).
On mine the internal splines are approx 1/8th" wide ,the mating crankshaft splines have a 1/4" spacing which leaves approx 1/8th" play when fitted ,got to be the wrong part hasn't it ?.
Hi Chilly...If the splines on the crank are wider than the internal splines in the sleeve then you do have the wrong part...I'm not sure which part you have though ....
The problem is many BSA models had this type of sock absorber over a period of a few decades and there are a number of different versions...Ian
Thanks Jeff
I think it'll be the middle one i need , thats an update on mine as it needs a separate spacer between crankshaft bearing and cush drive part , its the internal splines that are the problem with mine.
That photo and measurements explain something that was puzzling me. My original road engine which is currently still in the salt bike has the middle cush drive, I’d noticed how snug this was to the casing, there is clearance but not much. I have another engine I’m putting into the road bike, which came with the right hand cush drive but no spacer. I lined up the clutch and sprocket to see the size of the spacer, and was surprised that the cush drive inner face was quite a distance from the case face. The clutch is a single spring which I’ve modified to have a sealed bearing, after it got some damage so at first I’d thought I’d messed up the alignment of the bearing and clutch wheel. I checked the parts book to see the spacer is stated as 0.320 - 0.325. and that did align with roughly where the cush drive aligned. I couldn’t be bothered to pull the other drive apart to compare as I’m working during lockdown in my basement parking space so just too much hassle (for a lazy person!) but it’s clear from the photo that the lip on the cush drive is much thinner on the right hand version, so I’m feeling happier with the measurements. I’m now part way through slowly making the spacer from an old drive side outer bearing inner race, all done with a Dremmel (Ozito clone actually) on the parking bay floor, I’m about halfway through slicing the bearing inner to approximately the right width before a long slow job of finishing the cut face. If I’d access to the Kustom Kommune workshop I’m a member of this would have been done far quicker, but we’re at least another month before that will happen!