BSA Owners' Club Forum

The BSA Workshop => Singles => Topic started by: Dabbist on 31 October, 2017, 15:23:22

Title: B40 with B25 Cam
Post by: Dabbist on 31 October, 2017, 15:23:22
My understanding is that fitting a B25 cam to a B40 will (with the flat cam followers) give the same result as an SS90 cam, which is what I want to achieve.
According to RR and others the case will need machining to accommodate the cam followers and/or the greater base circle of the cam, I'm unclear on which or both.
Can anybody enlighten me on the nature of the machining?
Is this just a non-critical clearance problem that can be eased with a die grinder, or is it a precision job?
Also, the Otter site shows a custom bush for the camshaft. Is that a part which can be bought? I'm not sure my large and ancient lathe will be accurate enough to produce one :-[