So I’m may be selling my 05 CRF450 and probably looking at used 08 YZ450F. The bike is cheaper than all the used weekend warrior bikes if you add in that it has suspension doen and skid and rad guards and an exhaust , tires etc., and looks new. This bike has been ridden hard by a pro team but has also been maintained. They have torn it down and checked specs and replaced what was out of spec. Race parts were removed and stock parts put back in. It has suspension done, brand new fluids, plastics, drivetrain, new Twinwalls, DRD full system, all bearings greased, new tires etc. Oil was changed at 4 hour intervals. It looks brand new, and they do this every year and sell about 10-15 previous year team bikes and I have not heard bad things from all my searches It has almost 50hours on it, which I don’t like. They had some with less hours (30) but the price goes up and most are sold now. Because of the price I can afford to do a crank, piston, cam chain and bearings come this winter. I myself will probably put 50 hours on it before I get into the motor. Even if riden hard can I trust it to last another 50?? I know its rare but I don’t want it to grenade and cost me a cylinder, crank and head etc. How does the tranny and clutch hold up on these bikes?? After this season it will get rebuilt and hopefully be back to like new internal condition. What should be replaced: Crank, crank bearings seals, timing chain, piston & rings and then inspect the valves, seats and guides? My 05CRF had to have RHC valves and springs, Barnett basket, piston & rings etc. It runs great but now it has 150+ hours and I’d like to try a new brand. Any advice?