I have the opportunity to purchase a new white 08 YZ450, but after reading about the cam chain and tensioner problems I would like to learn more about this issue. My questions: Has the cause of the failure been identified as defective part(s)? If so, has the replacement part(s) been redesigned to correct the problems? After reading about this issue with the 08 YZ450 I would normally not even consider purchasing this bike but, the price is exceptional. I searched a bit before posting this but found very little other than a few instances of the failure, and no real solutions offered to remedy the problem.