Newbie Here!! just trying to help! i found this post on offroad.com, may be true? i have been following the posts on thumpertalk the past couple of weeks, and was doing some research and found this? Talked to Yamaha today... They don't know for sure but they think what happened was a "pinch" in the airline on the tool used to assemble that particular piece. Also a dealer I talked with today that has fixed 4 of these said a bike right out of the crate had 14 foot pounds on the nut and it should be 50. After the replacement and re-torque there have been to further failures. Mike Hobbs http://moab.off-road.com/pipermail/wr450.mbox/wr450.mbox heres the link where i got it from.