YZ450F - The bike that started the four-stroke revolution benefits from chassis and engine refinements that ensure the five-titanium-valved YZ450F remains at the head of the open-class pack. Subtle modifications to the aluminum frame and suspension mean light, precise, confident handling at any speed. New head and exhaust design delivers stronger low- to midrange power without sacrificing top end power. Ready to race straight out of the crate--with a ProTaper aluminum handlebar in adjustable clamps, titanium shock spring, gripper seat, Excel rims, etc. Five-speed gearbox provides maximum flexibility and the right gear for a wide range of riding environments.

New for 2008
Revised intake port shapes, and revised intake and exhaust cam profiles increase combustion efficiency for improved torque and throttle response in the low- to mid-rpm range. Micron-level adjustment of piston external diameter minimizes piston-to-cylinder clearance for reduced vibration and mechanical noise. Adjustment of gear backlash between clutch primary gears and balancer gears achieves further mechanical noise reduction. A new, larger-diameter titanium exhaust header with revised taper characteristics enhances exhaust efficiency. First "punched cone" muffler ever on a production bike allows 35 percent length reduction and 270-gram weight reduction while meeting AMA noise regulations. Matte black crankcase covers: light, strong and cool-looking. Steering head pipe and steering stem are 5mm shorter; lower forged triple steering clamp is lighter--for enhanced handling feel. Swingarm pivot stiffness is revised to complement front-end changes and further lighten and improve steering/handling. Changes to the shape of the outer fork tubes and revised internals result in improved damping and a smoother ride. Optimized linkage ratio provides a smoother ride and enhanced rear wheel traction. New, YZ250F-style, front-brake caliper (-220 grams) and a lighter disc remove unsprung weight and provide excellent stopping power. A new axle and collar remove additional weight. A 120/80-19 rear Dunlop D756 knobby replaces the 110/90-19 for even more traction. A D742FA replaces the D739FAL front tire. Wider footpegs provide excellent boot traction and rider comfort.

YZ250F - Ongoing refinement to chassis and engine produce an amazingly balanced, light-handling machine with performance that's accessible to all levels of riders. Five-titanium-valve engine with increased compression spins out even more torque and horsepower. A carefully tuned aluminum frame made up of forgings, weldings, castings and tubing means sharp, super-precise handling. Mass centralization provides fantastic overall balance and performance. A ProTaper aluminum handlebar in adjustable clamps, Excel rims and a titanium shock spring are just a few tricks up the YZ250F's sleeve.

New for 2008
A redesigned piston bumps compression ratio from 12.5:1 to 13.5:1, further exploiting the inherent efficiency of the five-valve combustion chamber. Carburetion and ignition revisions complement the increased compression. Adjustment of gear backlash between clutch primary gears and balancer gears reduces mechanical noise. Changes to the clutch boss and primary driven gear improve clutch oiling for excellent durability. Matte black crankcase covers: light and cool-looking. Changes to the shape of the outer fork tubes and lower triple clamp, and revised fork internals, result in excellent handling, great damping and a smooth ride. Optimized linkage ratio provides a smoother ride and enhanced rear wheel traction. 55mm stainless steel footpegs replace 45mm ones for great grip and comfort, and a new brake pedal eases operation. Grippy new Bridgestone knobbies front and rear.

YZ250 - Our legendary two-stroke Supercross winner is more potent than ever. 500 grams off the front end makes this the quickest turning, best-handling YZ250 ever. A light, aluminum frame housing a patented YPVS™ Power valve-equipped ripper of an engine results in an awesome power-to-weight ratio. Ready to race out-of-the-crate, complete with a ProTaper aluminum handlebar, titanium footpegs, gripper seat and Excel rims.

New for 2008
New, YZ250F-style front-brake caliper (-220 grams) and light, wave-type discs (-70 grams) front and (-70 grams) rear remove unsprung weight and provide excellent stopping power. A new, pushrod-type front master cylinder with a smaller piston and a redesigned brake lever serve up great feel and braking power. Modifying thickness of both inner and outer fork tubes in the 48mm inverted fork result in a weight reduction of 200 grams. Revised damping settings provide fantastic bump absorption and comfort. A 120-gram lighter fork protector, lighter axle and axle bracket, lighter wheel collar and the new front brake add up to a 500-gram lighter front end--and even quicker, lighter handling. Revised rear shock settings complement the ones in the fork.