My Star twin is a 1949 plunger model currently fitted with a short-stroke 500cc engine. I have toured France several times with the original long-stroke engine but in July 2011 the gearbox locked up, the grub-screw securing the gear selector shaft fell out and the shaft moved into the gearbox sprocket and jammed.
The bike is now attached to a sidecar, but need to change the rear wheel sprocket as it is too high geared, Does any-one have a 49T sprocket ?