The YFZ450X comes with a newly designed front suspension. The front A-arm is shortened 43.9 mm to
395.2 mm — optimal dimensions for tight courses and the new suspension while still ensuring a full range of motion. The front KYB shocks are now 426 mm long versus the 462 mm length of the YFZ450R. The easy to adjust damping goes unchanged. As a full package, the new suspension settings, A-arm design and trail track width allow the YFZ450X to soak up bumps while also allowing the rider great handling through tight, technical terrain.The gravity-cast aluminum rear swing arm is matched to a fully adjustable 46 mm KYB piggyback shock affording the rear wheels 11 inches of travel.POWER AND PERFORMANCE The YFZ450X features the powerful titanium 5-valve DOHC liquid cooled single cylinder 449cc engine using the cylinder head and cylinder from the championship-winning YZ450F motorcycle. The titanium five-valve cylinder head comes with camshafts designed just for ATVs that hammers out superior low- to mid-range torque and pushes through to a high-revving, hole-shot grabbing top end.Like its track-dominating brother, the technologically advanced 450X is also equipped with electronic fuel injection featuring a 42 mm Mikuni throttle body, 12-hole Denso injector system and a Mitsubishi 32 bit ECU, which provides exceptional atomization of the fuel for maximum power, unrivaled throttle response and automatic altitude and temperature adjustment. For 2010, the YFZ receives a new FI setting specifically designed for those situations unique to technical woods riding. The system also includes idle speed control for easy, reliable startup. A stainless steel head pipe with a titanium heat shield and a new oval muffler provide maximum performance while keeping the YFZ450X well below recommended noise limits.CAST ALUMINUM FRAMEThe new YFZ450X features the lightweight, no-weld cast aluminum frame exclusively from Yamaha and first introduced on the 450R. The frame’s high tension-steel bottom portion helps keep the engine as low as possible, centralizing mass for optimized handling. The cast aluminum frame is bolted together, rather than welded, for maximum durability.SIMPLE SERVICE ACCESS AND RIDER COMFORT Like the 450R, the all-new YFZ450X has the benefit of years of Yamaha Factory Racing experience – on resulting highlight is simple race prep and service. Body panels come off easily, and there is no need to remove the battery or other components to take off the fenders. The oil tank is integrated with the crankcase so servicing the engine is a snap.The YFZ450X also boasts ProTaper handlebars with four-position adjustability, allowing riders of any size to find a comfortable setting. The seat design is thin yet roomy in the front and wider and more padded in the back for a more comfortable all-around ride. The YFZ450X also comes with large 65 mm wide foot pegs with kick-ups that provide maximum traction and added comfort when moving around on the machine.WHEELS, TIRES AND STOPPING POWERIt should come as no surprise that YFZ450X has shaved a few pounds off as well. In addition to the weight saved with the reductions in the rear axle and front A-arm and suspension design, the front and rear wheels have been updated to reduce weight while also increasing structural rigidity. With the seam of the wheel now rolled inwards, not only is the wheel more rigid, it is also prevents debris that could otherwise build up after a day of riding. In all, five pounds have been scrubbed off the overall weight of this model bringing the YFZ450X in at 400 pounds.Those new wheels host Dunlop radial tires with a superb combination of compound, tire profile, tread pattern and sidewall-to-tread center stiffness to provide outstanding comfort, bump absorption and precise cornering performance. At 20 inches in the rear and 21 inches in the front, the tires also provide maximum ground clearance for any debris that may be found along the trail.The YFZ450X has excellent stopping power from dual front hydraulic disc brakes and a lightweight wave-type rear rotor including dual piston calipers in the back as well as the front.Rounding out the ATV’s top features is an instrument panel located on the fender in front of the rider including vital indicators signaling low fuel, coolant temperature, check engine, and neutral gear in a straightforward LED display.The new YFZ450X comes in a standard color Team Yamaha Blue/White or in a second color Red/White. A Bill Ballance Special Edition model comes with a special color pattern, graphics, wheel color, shock color, SE badging, a GYTR front bumper and Bill Ballance-inspired #1 plate.