Hy Guys
It has been a while since last posting. I've been slowly tinkering away on M20-109711. I now have almost everything i need to finish the project. I have found that my drive side crankcase bearings are roller bearings. I have searched trough previous posts but not found any coments on have 2 load bearing rollers fitted. I was just going to replace the outer bearing with a ball race as per the work shop manual.
1 I just wonder if there is anything i should know or could be missing before i continue?
2 Is there any advantage in 2 load bearing rollers fitted?
3 i was also going to carry out Ian's sugested modification for lubricating the drive side bearings,

Any coments greatly appreciated
Cheers
Phil Smith
New Zealand

email (option): wpgarage@xtra.co.nz

No, your right putting a ball race in where it should be, that's what holds the crank in position, that's its main job.

I also found one engine with 2 hoffmann roller bearings fitted to the drive side.

email (option): kalle.tikas@gmail.com

Me too, and they are double lipped so have the same function of positioning the crankshaft. They were in early engines so they probably started with rollers and changed to ballbearings later.?

Regards, Michiel

email (option): m.wijbenga@hotmail.com

Norton Commando's have 2 roller bearings, you measure the end float and if needed, shim the crank 5-10 thou.
I'm in the middle of doing my 16H crank and I've put a roller each end for extra strength and junked the swivel ball bearings. But the 16H has 2 drive side bearings so the other one is a ball. But even with 3 ball bearings the service manual tells you to check the end float and shim. The crank will still slide in the bearing.

email (option): horror@blueyonder.co.uk

Hi Horror,

No need for those big tyre levers on a BSA crankcase In the BSA construction all inner bearings, washers, spacers, etc on the driveside shaft are clamped together when the outer nut on the shaft is fastened. This construction is possible because of the use of a splined shaft instead of the taper used on the Norton and earlier BSA´s. Regards, Michiel

email (option): m.wijbenga@hotmail.com

Phil, don't forget to let us know how you get on.