This is a brand new kick start ratchet and pinion gear.
Ratchet pinion gear measurement:
Outside Diameter: 1 1/2″
Inside Diameter: 13/16″
Fits: BSA M20, M21, M33, B31, B32, B33, B34 from 1938-63 Plunger and Rigid models frame.
Part number: 66-3079, 66-3080