Smith, you bring up a good point about build-up on the valves. The last time I did a valve check they were on the loose side, meaning the clearance was greater, but they were still in specification. At the time I thought I was getting some normal valve train wear, but now I'm thinking it could be a coating on the face of the valves from using CD2. I don't know if this is a good thing or bad thing, it may even be a way to keep the valves in check. I wonder what the chemical is in CD2?? I bet it's not lead. I got the bike used, it had less than 10 hours on it, and it still has less than 60.