greetings, im a newbie to this site but not restoring bikes but this is my first WM20, originally from Scotland i now live near Vancouver in western Canada, as soon i can fix the problems with my photobucket i will attach some pics
for the moment i have Darren trying to help with bearings, my bike is a 1944 engine and frame number 110521 the engine being overhauled in nov 52 and it seems to have the later crank in it and thats where help is needed, i see there is numbers for the 4 crank bearings in the technical section but trying to convert them to modern numbers hasnt been easy, does anyone have the current bearing numbers that are known to work
cheers
Kevin
For what it’s worth, I’m able to quickly find all 4 crankshaft bearing online using the numbers given in the Technical section...
The 2 roller bearings are not inexpensive, no matter where you look, but the 2 outboard ball bearings seem to be quite reasonable and readily available.
my local parts guy (kid) is trying to source them and also says that 2 of the crank bearings that have different numbers in the tech section actually cross over to be the same bearing, id just like to know the part numbers that are available now from someone that has actually installed them in their engine
Also all the bearings that came out of the cases have different numbers than in the tech section too
There are cast iron and steel M20 cranks in different years but all wartime engines had the steel crank...Only engines from 1936/7 have the cranks from before the Val page/Herbert Perkins redesign when most of the engine parts differ anyway and are not interchangable...
All wartime and post war engines use the same main bearings and IMO it's not worth thinking about any non branded bearing. Japanese, American or European branded items are the way to go...It's worth noting here that it's best to replace the drive side outer ball bearing (6205) with a rubber sealed bearing (6205 2RS), removing the inner seal that is on the crank side before fitting...I would also replace the BSA bearing retaining circlip (which should only be used once anyway) with a 'modern' pattern circlip with 'eyes'...It makes fitting and removal far easier..Also ckeck the oil flinger plate is flat and unworn and that the main bearing spacer on the drive side is within limits (1.000"-1.005" long) before reassembly...Ian
I think you will fall in love with these old war horses. They are very easy to work on and parts are plentiful. I would suggest you visit the technical section of this group because a lot of information you seek will be there already. There is also a for sale page. Another great resource is Draganfly Motors. They sell almost any part you need and their shipping rates are very reasonable. They have parts books online that show you what you need and assembly order.
