I know chains have been improved substantially over the last 50 years but I ran a Vincent Shadow and Steib sidecar outfit for 30 years (between the mid sixties and the mid nineties) and with hard driving and sometimes pulling a camping trailer, although the engine was only rated at 55BHP, after about 5000 miles, even with regular miantenance, the rear chain looked like a bit of knotted string and had to be replaced.
Regards
Keith
