I have a 1983 KX500, yes an old air cooled monster. I put a new OEM piston in and immediately fried it. It made one lap at Southwick pinging and detonating miserably before it quit. Kawasaki had single ring pistons in the KX500 thru 1987 I think. My piston is a single ring design and no longer available from Kawasaki. The bore/stroke are same as the later 1988 on up models and my question is does anyone have experience or think a currrent double ring KX500 piston would work in my 1983 KX? Also, the piston siezed on the sides so I guess it got hot. The pinging would suggest I need timing adjustment and/or head modifications. Any thoughts? Detonation was a chronic problem for this year/model. I have a PVL ignition and set the timing based on the specs but still have these problems. thanks