Thanks Woodsy...yes, it had been knocking quite a bit, so more than likely, you hit it right on the head. We have been running 32:1, so it was oily enough that it probably prevented a major meltdown. Guess premium pump gas is out, and VP racing gas is in huh? Thanks again.
Perhaps most importly however, is where I can get a replacement piston, and pronto?! The whole point of fixing the gasket (which revealed this problemo) was that this coming weekend is my first ride after two months off with a broken wrist. I will be very bummed if I have to sit it out.