Had a chance to ride an 03 WR450 this week.Borrowed the bike from a gentleman who works for a major motorcycle company as a rep, Not Yamaha. Had split the key twice and repaired by one of the local bike shops near North bend in WA. Dragged it out to Bellfair, east of Seattle. Nice ride until it backfired in the middle of a corner and spit me off over the bars. What is the cause as you on this site see it? anyone got a handle on a fix? Been thinking about a new WR450 and after the 1 mile push, Up hill, I am having second thoughts. Funny, My Cannondale never quit running, overheated, leaked, broke and it handled better than the WR. Maybe a WR with Ohlins after yamaha gets them to run more than 15 miles at a time.