10-05-2021, 12:16 PM
I'm sure one of the motor cycle engines that I have tinkered with, a two stroke, had a pin in the ring grooves, with the ends of the piston rings ground to a semi-circle to match it, thus preventing the rings from rotating. Can't for the like of me remember which is was. Probably a Lambretta, or a Bultaco or perhaps even a Yamaha. It was a long time ago.Like this: