All good and correct info the only part not covered are the different types of rings ie: reverse torsional,bevel back,beveled. all rings will rotate. If you have a vibration problem you'll find them all the gaps coming to the same point. The rings seat at the ring land as well as the bore surface. They use a combination of physics already in place in the cylinder,as well as the film of oil in place on the cyl wall. Would reusing old ring work? I suppose it could but I've never tried it in two stroke engines. Too much work to take a chance.