I only ask because im doing some work on my 08 450. new piston, cylinder, valves, cam chain, tensioner....etc. (top end stuff) its got 180hrs on it. never had an issue but one of the mechanics said even that theres no play on the bottom end bearing, its gonna be ready to blow anytime around 200hrs. I thought this to be strange. maybe a way to get me have him rebuild it? my '98 400 had who-knows-how-many hours on it. never opened it. my 2000 426 had another who-knows-how-many hours both desert and supermoto and never had to open it up..... so what s a realistic expectation to have for a modern 4stroke in terms of the crank longevity? i wold think with good maintenance the bottom end should last a lifetime. I clean air filter before every ride, and oil and filter every 3 hrs or so.