I have experienced this clutch problem as well. I took the whole clutch apart and found that everthing looked new, except for very minor scratches on the cover side of the pressure plate. I couldn't find any corresponding scratches on the clutch cover either. At the time I took it apart, I had been running Yamalube 4. Since then I have switched to Mobil 1 15w50 and I have not noticed a difference, for better or worse, with the clutch. I do know that if I warm the bike up real well, I get very little if any chattering. I haven't had much, if any, of the grabbiness that I've heard other people have. My bike is long out of warranty, I got it in December, and since the clutch looked pretty much new when I pulled it out, I have been trying to warm it up good and trying not to worry about it. It's funny, I didn't start hearing the chattering sound until the bike was about 2 months old. I'll just take it day by day. Tuner had posted a while back that he heard that Yamaha was recalling the clutch, but I haven't heard anything else about it. Please keep us informed of your findings.