I bought a load of BSA spares recently and included in the boxes were some 1925/26 bits.
24-28 crankcase drive side for 1925 4.93hp and 5.57hp models
Inside it is 24-55 exhaust cam pinion
24-53 inlet cam pinion, and 24-61 exhaust valve lever.
There is also a matching crankcase for the gear side cant find a part nimber for it but it has an engine number stamped on 5216.
Also have a crankcase timing case for these crankcases part no 24-30
(Ive also got a box of gearbox spares but not sure what these are yet.)
Spares are in Leicester, UK and I would like £100 for this lot.
Now sold on ebay.
I do still have a number of pre war gearbox internals mostly 1920's stuff I think. Steve