I am working on the brakes of a 1957 B31 with Ariel full width hubs.
I read recently that not all Ariel full width hubs are the same ie the hubs on a Norton might be different to say this BSA etc; even though they appear similar.
Looking at the BSA parts book a "Brake lever and camshaft spindle assy" is listed. Interestingly on this bike the lever and cam assy are two seperate parts.
The B31 is of unknown history; so it might be, if the above is true that the hubs were once fitted to a different marque.
The brakes work fine, just curious thats all.
Anyone shed any light.