This new "X" version of the fuel injected YFZ450 has a narrow track chassis for tight woods and trail performance.


Where the YFZ450 R has an extra wide track for motocross racing, it wasn't really designed for woods riding, and in some cases might be too wide for a particularly tight trail. So if you wanted all of the great new features on the latest YFZ for hare scrambles or cross country racing, you would have had to modify the ""R"" version... until now.


The YFZ450 X has all of the same great features as it's "R" sibling, including the powerful 5-valve 449cc race engine that had been updated in 2009 with fuel injection and a bunch of goodies from our YZ motocross bikes. This high performance engine is cradled by the same hybrid aluminum chassis as the 450 R for improved strength and reduced flex, making the new YFZ450 X the most capable woods racer we've ever developed.


The YFZ450 X also has the same top shelf long-travel suspension components as the 450 R, with triple adjustable shocks, gull-wing style front a-arms and a super strong gravity fed aluminum rear axle. The 450 X also shares the latest 65mm wide footpegs, controls and cushioned body panels, not to mention the most powerful brakes around.


So what makes the 450 X different? Well for one it is 3 inches narrower than the 450 R, so it's going to be a lot easier to navigate through the tight trails. And the suspension settings have been modified to better match woods style riding. The X model also gets new rims that are even lighter than those on the 450 R, and with less overall mass the 450 X will out accelerate and out brake the wider 450 R.


Other than that, they are pretty much the same. Both designed to dominate the competition... one on the motocross track, the other in the woods.


Fuel Injected 4-Stroke Engine: Dual Over Head Cam (DOHC) 449cc 4-stroke engine retains a 5-valve head for optimum high RPM power. Many of this engine's design elements have come directly from our YZ motocross program, including the cylinder, cylinder head, cams and crank designs. Engine power and mid-range response are both improved over the carbureted YFZ engine and with the addition of fuel injection, engine power is always optimized, regardless of altitude or temperature.


Engine durability was improved over the old carb versions as well with beefed up crankcases, a large diameter big end crank bearing, stronger connecting rod and a smoother counter balancer.


Yamaha Fuel Injection: Yamaha Fuel Injection (YFI) uses a 12-hole injector that provides exceptional atomization of the fuel for maximum combustion efficiency and power delivery. The system also uses a big, 42mm Mikuni® throttle body and includes ISC (Idle Speed Control) for easy, reliable start-up and warming. YFI constantly monitors variables such as air temperature, intake pressure, engine temperature, throttle position and more, to ensure optimum fuel delivery. YFI automatically compensates for changes in temperature, elevation, and even barometric pressure. This means you don't have to fool with carburetor jetting, so you can focus on the ride.


Hybrid Aluminum & Steel Frame: The frame is designed of lightweight aluminum, with a tension-steel bottom frame that lets the engine sit lower for excellent mass centralization. The lower frame is made from strong high tensile steel, since that portion typically takes the majority of abuse from rocks and debris. This hybrid frame also incorporates a "Zero Weld" design for maximum strength.


Narrow Stance: For trail and woods riding, a super-wide race YFZ450R can be bulky and cumbersome. The YFZ450 X is 3 inches narrower, specifically designed to be more nimble for tigh trails and cross country racing. This narrow stance allows for quicker handling and will allow the 450 X to go places where the 450 R might no fit. The front A-arms still incorporate the "Wide Arc" design to greatly improve ground clearance, so obstacles are less likely to impact the lower a-arms. They are just a little shorter than the 450 R to keep the stance narrow. Upper and lower a-arm pivot points are close together to reduce the pivot angle for superior suspension control.


High Tech Long Travel Suspension: Piggy-back reservoir front shocks are extremely robust with 44mm rods and a Kashima coating for reduced friction. In the rear the cast aluminum swing-arm provides up 11" of travel from the long-travel fully-adjustable piggyback shock. All three shocks (front and rear) have high and low compression, rebound and threaded pre-load adjustments enabling you to tune the ride to the conditions.


Spacious and Comfortable Ergos: A wide-back seat provides the perfect balance between comfort and movement. It's narrow in the front for easy transitions from side to side, but wide in the back to help cushion the landings and rough corners. And even though the YFZ X has long suspension travel and a race oriented seat design, seat height remains at a low 31.9".


Racing Controls: ProTaper® handlebars are mounted on 4-way clamps for exceptional adjustability. There are two sets of holes in the handlebar crown, and eccentric clamps so the rider can choose the standard setting, 10mm or 20mm forward, or 10mm back. The thumb throttle is designed to minimize effort. The front flip-type parking brake is removable for racing. The front brake lever is adjustable and the clutch lever is adjustable on the fly.