I have about 1300 miles on my belt. The machine no longer wheelie's and seems a bit slower than it was. Top speed is also down a lot(68-63). Has anyone changed there belt and seen an improvement with performance? I hate to spend the money on the belt if I don't need one. Oh yeah, I have no more shims in the clutch to adjust.

 

Doesn't sound like necessarily a belt problem to me. Does it "squeel" when you get on it from a dead stop? (If YES then it could be, but I have never heard of a P650 belt stretching that much.) Does it ever "squeel" when in in gear and at a dead stop? (Most do at some time or another, regardless of belt age with all shims removed; this is a good thing.) I'm just fishing here, but make sure your air filter is clean and try a tank of 92 or 93 octane and see if you can't get those front wheels off the ground.

Good Luck

 

My first belt got so narrow from turning the mudzillas in only 500 miles that removing all the shims wouldn't tighten it within the spec.

Tightening a belt affects takeoff gear ratio, and has no effect on top speed.

Belt length and width both have an effect on top speed. Longer and narrower would mean less speed.

 

I run 93 octane al the time, filter was a little dirty but it's been worse after a long ride. Belt does squeal everyonce in a while taking off, so I thought it was loose, but then sitting still idleing the machine felt like it was surgeing, I lowered the idle speed a little and it doesn't do that anymore. I have a new Rincon in town and want the Prairie in top shape before I ride with him. I guess I'm going to have to buy a new belt and try it