Anyone done their top end on their 400 yet? I'm just wondering if it is wise to start thinking about it at 3000 miles which is my next ride. If not, what are the signs that may point to needing this done? On another subject, on my last ride I noticed a new sound that was new to me. I'll try to explain it the best I can. Whenever I was slipping my clutch, I would here a sort of high pitched "air suck" sound from the engine. It would go away when the clutch was pulled all the way in or released. I'm not sure if "air suck" is the correct way to put that. I'm wondering if I am starting to lose my clutch. Any Ideas?