Well I picked up a 2008 YZ450 the other day for super cheap. Guy that had it said it will push start and run perfect, but wasn't able to kick it over. Looked up what issues this might be and found the automatic compression release could be the culprit. I'm just wanting to know if this is a common problem with these bikes, and if an aftermarket cam chain tensioner would help it to not happen as frequently. Got the bike for a pretty good deal as clean as it is too....... any help is greatly appreciated.