mark my words, you might find out that alot of the belt problems are that the secondary spring is to long an binding, when the belt drives up the drive clutch and goes down the secondary an hits a wall because the spring is binding and stopping the belt from going down an when you keep on the throttle to go faster and the primary keeps trying to push the belt up, kaboom goes the belt, fix for the secondary spring binding because its to long is to take 0.20 of the plastic washers on the end of the secondary spring, this works for some but not others, also it is to be said the the 083 belt is to short and being pulled apart trying to get to full shift out, this is on the procross 8 but could be some of the problems with m's also, most of the guys running for mph are adding alot of weight to the primary to get the sleds to mph an belts coming apart like as in if you keep pushing the primary to push the belt up and down into the driven an its binding in driven or belt is to short, kaboom, i say it right now that the new 083 belt will be longer when they come out, they might not be call a 083 tho