I went riding this past week after just servicing my 06 yz450 and landed a 60 foot double and the bck tire just locked up, i looked at the wheel and the hub just expolded! I know it was not because of over tightning the chain or the bolts coming loose because i had just checked everything about 30 min before all the carnage. Before the hub broke i have always had trouble keeping sproctet bolts in it, i use grade 10 ironman bolts, and coat the whole bolt with locktite. About every other time of riding they come loose or are completely missing. Yamaha used the same hub on the 450s and they do on the 125s...i think that is crazy. Thats just asking for trouble. They definatly need to recall them and strengthen the hubs on the 450s!