I have to add, this happened to me. Last year I put an 1.375 on my zr 600, started ratchetin. Keept tightenin track, till it was too tight. Knew that was wrong, thought it may just have been too much traction for the sled, put anti ratchet drivers on. Heres where it gets interesting. Ended up stabbing the track runners through track with anti ratchets on. Damn near put buddy in hospital that was riding it. Anyway, took back apart, for another track installment. I should say that we were having troubles getting the drivers to go on and off the drive shaft to start with. Got to investigating a little and the driveshaft just didn't seem right, layed on a straight and thought it was a little off. Took it to a welding shop to have them check to see if it was square. Ended up being tweeked 1/16 of an inch. They straightened it and no problems since. Also sled has never been wrecked, so not sure if this could have been a factor defect or what, just something to check.