Hi Ian, yes I checked the cable run and condition first up, all is well. Next is to drop the case & check clutch adjustment. It definitely doesn't slip, may be adjusted too tightly, soon see. Lots of replacement levers on ebay, but of course no indication of pivot measurement. Can you suggest a source for a 7/8" pivot clutch lever assy? There are plenty of soft pull levers with up to 3 settings, but they would look too weird on a BSA for my taste.
Cheers, Mike