Last year, the KX450Fcame out guns a blazin', joining Suzuki and Honda with fuel-injection, and nearly knocking Big Red's CRF450Roff its high horse (eight consecutive CW Ten Best wins). You would think that the comprehensive redesign the KX received last year would get it through more than one model year, but it just doesn't work that way in the MX world. So for 2010, Kawi has once again dramatically updated its big Thumper. Among the major changes are a bridged-box (slipper-type) piston, new crankshaft, camshaft, clutch, ECU, radiators and exhaust. And that's just the engine! The chassis got a new fork assembly, shock, swingarm, chain, brakes, front fender, firmer seat and Bridgestone tires.