BSA L29 Bearing problems

[rick]

Hi All,

I'm in the process of rebuilding the engine on a 1929 BSA 350cc Sloper. I have two problems so far

1) I cannot see how to remove the out race of the crank shaft roller bearing nearest the casing it sits almost flush with the end of crank case its self, there are two small what I would describe as drill holes partly made on either side of the casting which allow a very small gap between the casting and the bottom of the bearing outer race I can only guess it's there for some sort of extracter. Has anybody got any suggestions on how to tackle it's removal with out using heat.

2) I have managed to get hold of a bearing to replace the one mentioned earlier, unfortunatly it require's two slots about 1/8" wideto be machined in front of the iner race bearing holder to match up with the drive dog on the out side of the engine this dog has two small tags on it which marry into the slots of the bearing front face. I have been told its virtually impossable to machine mill these slots into the hardended surface of the bearing race face. Is this true or are their any tricks of the trade. Any advice would be appreciated

Rick

[33d6]

I would suggest you get yourself a copy of Service Series No 23 printed on pages 78 & 79 of 'MotorCycling' for May 19, 1955. This specifically covers the 1928-32 Sloper BSA's and should help. Amongst other things it makes a point of specifying the roller and ball races used on the crankshaft. As they are metric sizes I wouldn't expect any great trouble to get them.

Oddly enough these are absolutely standard races without any of the slots you mention but who knows what previous owners have had to do to keep your bike on the road over the years.

As for machining the hardened surfaces of ball races this is easily done with modern machinery that didn't exist when the bike was new. The advice about not being able to mill the slots without annealing and heat treating the steel is basically correct but nowadays such a job would be easy meat for an EDM (spark erosion) machine. Wouldn't like to think of the cost though.
Cheers,