I sincerely appreciate your comments. I've owned quite a few 2 strokes, and while the compression may still be +100, that rattling is making me a bit nervous. Like I was saying, it seems to settle down after she gets up to temp. I might just sell it like it is though and make it the next guy's problem.

The bike had a bad petcock and I think the gas in the crankcase might've washed down the walls. I'm totally speculating though.

Anyone want to buy an NSR with a slightly rattly topend?

RZ Rob