a quick question on getting tye gearbox outer cover off. It seems 2 types of gearbox available depending on engine serial, mine is xm20 5899. I have all facing screws off together with gear lever and kick-start. The cover is reluctant to move. I see there are bolts behind the cover on backside of box. There maybe 2 small and one large . Do I need to remove these?
Cheers Ron, your not wrong; they were bloody hard to get at. However, i only had 2 x 1/4 inch nuts and the larger one axial to shifting shaft which I didn't remove. The whole lot came off OK, once I noticed the circlip! When the cover was off it looks like I needn't have removed the nuts at the back of the box at all! They seem to just hold shifting mechanism in place.
The main find was a broken kick-start spring which I am on the hunt for next. I did notice no gasket, just cement. I read somewhere that the gasket was an important part of the clearance of some shafts. Is this correct. No oil seals were a surprise too !
Again I can't speak for the post war box but I think they are essentially the same. On the WM20 box the thickness of the gasket between the main shell and inner cover is important as that will alter the end float of the shafts. Ron
As it's a '48 bike have you got the later gearbox with the speedo drive?..If so the details for attaching the outer cover differ from the WD models....Ian
It looks like I definitely have a later gearbox. The speedo drive was a clue but not the full story. I used draganfly's site/drawings and ordered 66-3058 and the gasket from same drawing. Gasket was correct but spring slightly too big all round; 2 1/2 " rather than my 2 1/4" and thicker guage wire in its construction. I tried fitting it anyway but no good as overall depth pushed starter shaft off it's natural seat.
A couple of pics to draganfly and they identified my box as a 1950-62 possibly from A,B or C models? This might explain an earlier anomaly of it have 3/8" final drive chain and sprocketry instead of 1/4" ??
Ian yes the rubber bush was well shot and I got one them OK.
I reckon I might still need to get clutch off as I think even once starter working the clutch was slipping preventing decent action through to crank.
Do I need some special tool to get clutch off; spring presser of some type?
