As stated above is probably what's happening. Happened to me last year a few times when the track came unloaded. I started last year with ski doo clutch components(only thing out there) and even tho I loaded it heavier with heavier ramp and heavier spacers it happened occasionally. I run 2 gallons of Av per tank and good non ethanol 93. This year I switched to sled head racing ramps(full clutch kit)loaded all the way and number 3 spacer weight, clicker 2 at 7-10,000 ft. I'm running around 8-8100 rpm at all elevations and conditions, up 4-5mph track speed to 52mph from 47ish. No blown belts and cooler clutch temps. Im at over 1000 miles on kit and in my opinion the best setup I've rode or ride with. Everyone can talk about how there turbo kit has ecu programmed or run a piggy back controller etc but if you don't have your clutching dialed it's all for not. Then you have the blend of fuel to deal with as well. To much race or Av and it feels lazy and rich and response goes to crap(once again doesn't matter which kit you have whether piggy back or programmed ecu) to little and you burn it down. I have no affiliation with any product manufacturer and have ran all there kits in the past. Loving my mpi 850 :face-icon-small-hap