2021 Yamaha YZ 450FX

YZ450F™-Based GNCC® and Hare Scrambles Focused Racer
The YZ450FX™ is developed from Yamaha’s flagship motocross model—the YZ450F—with many added features and unique settings that make the YZ450FX the ultimate GNCC®/Woods racer.

Yamaha Power Tuner App
Yamaha’s free of charge and industry-exclusive Power Tuner app puts the flexibility and precision tunability of the GYTR® Power Tuner into your smartphone. Make fueling and ignition timing changes instantly and upload them to the bike for the ultimate in track-side tuning.

Adjustable Engine Mapping
A handlebar-mounted map switch allows the rider to quickly select between preloaded engine maps—loaded and configured in the Power Tuner app—to account for changing track and weather conditions. Map 1 provides more responsive, quicker revving engine characteristics while Map 2 provides smoother response, slower revving characteristics for when traction is limited.

Electric Starter System
Utilizing a compact starter motor and ultra-lightweight lithium battery, the YZ450FX maintains the convenience of push-button starting for effortless restarts under pressure and relaxed riding when the clock isn’t ticking.

Potent Fuel-Injected Engine
A high-compression cylinder head, forged piston, aggressive cam profiles, cylinder geometry and much more work together to give riders the ideal power spread in challenging GNCC® racing conditions.

Class-Leading Suspension
Yamaha uses KYB® spring-type forks on all of our YZ® models, with industry-leading function and easy set-up at the track—these forks are ready for the top step of the podium straight out of the box.

Rearward-Slanted Cylinder Design
The YZ450FX’s distinct rearward-slanted cylinder design—complete with rear exhaust and forward-mounted intake system—features a cylinder head that works with the frame geometry for optimized weight distribution. Inside, the engine features a straight intake tract, aggressive cam profiles, a high-compression “box bridge” piston design with DLC-coated piston pin and more. Finally, the YZ450FX features specific ECU settings to suit the needs of cross country riders.

Electric Starter System
The YZ450FX features a compact electric starter system to minimize restart delays on track and add convenience everywhere else. Powered by a high-capacity and ultra-lightweight four-cell lithium-ion battery, the system adds minimal weight.

Yamaha Power Tuner App
The free of charge and industry-exclusive Yamaha Power Tuner app brings the power of the GYTR Power Tuner to your iOS® or Android® device. Using wireless connectivity to talk to the bike’s onboard CAN-bus network, the app allows owners to adjust air/fuel mixture and ignition timing maps to tune engine performance for track conditions, record race log information and monitor a range of data such as maintenance and system diagnosis, engine run time and more.

Adjustable Engine Mapping
A handlebar-mounted map switch allows the rider to quickly select between preloaded engine maps—loaded and configured in the Power Tuner app—to account for changing track and weather conditions.

Advanced Fuel Injection
The engine breathes through a 44mm Mikuni® throttle body fed by a high pressure electric pump to ensure optimum fuel atomization and power for a wide range of riding conditions.

Robust Transmission and Clutch
The YZF450FX’s wide-ratio 5-speed transmission enhances cross country performance for more flexible gearing selection in open terrain.

Aluminum Frame
The upper frame bracing provides rigidity and durability while rear frame spars and cross country-tuned engine mounts centralize mass for the best possible balance of bump absorption, stiffness and rider feeling.

Compact Body and Seat Design
The YZ450FX features stylish bodywork from tip to tail, including a large 2.15 gallon mass-centralized fuel tank. The body design is narrow for more comfortable knee grip and control feeling while the narrower and lower seat gives the rider additional room to move aboard the machine.

Class-Leading Suspension
The industry-leading, fully adjustable KYB® coil spring-type fork with speed sensitive damping provides exceptional balance between handling and bump absorption for race-winning handling performance. The linkage type rear suspension uses a KYB® shock with specially-tuned damping characteristics to match the YZ450FX chassis with both front and rear system settings for optimal GNCC® performance.

270mm Front Brake
Large 270mm front disc brake coupled with aggressive pad material offer outstanding braking performance and machine control with exceptional stopping power and controllability.

Cross Country Wheels and Tires
The YZ450FX features enduro-specific tires for the ideal balance of traction and durability, complete with an 18-inch rear wheel. Each wheel’s cross-sectional profile is computer-designed to shave valuable weight without sacrificing durability, too.

GNCC®-Focused Details
The YZ450FX includes a range of cross country specific upgrades compared to the YZ450F motocrosser including a composite engine guard, 18” rear wheel, sealed O-ring chain, fuel level warning indicator and a folding aluminum kickstand.

Adjustable Handlebar Mounts
The 4-position adjustable handlebar clamps are rubber mounted to improve comfort, reduce handlebar vibration and allow riders to adjust the bar position while the oversize 1-1/8” handlebar is strong but lightweight.

Embedded Graphics
Yamaha’s unique embedded graphics are built into the bodywork for extended durability, resisting both peeling and damage.

All-New Cylinder Head
The YZ450FX's already potent motor was treated to a host of go-fast refinements, including new combustion chamber geometry with steeper valve angles, more aggressive cam profiles, a higher compression piston with low friction rings, longer connection rod, larger exhaust head pipe connector, a high flow air filter, more efficient breather system and more—all while fitting under a smaller and lighter magnesium valve cover.

Revised Bilateral Beam Frame
The YZ450FX aluminum frame features all-new flex characteristics that give riders the ultimate combination of precise cornering performance, traction and bump stability. By tuning the rigidity balance of the chassis with changes to the lateral beams and engine cradle tube thickness as well as engine mounts, top triple clamp and front axle, the 2021 YZ450FX takes rider confidence to new levels.

Updated Suspension Tuning
The 2021 YZ450FX features revised front and rear damping tuned in concert with the updated chassis to improve cornering performance, traction and bump absorption. With smoother chassis movement, the rider is able to make the most of the engine's exceptional power with greater confidence.

New Braking Systems
A new, more rigid front caliper and compact rear caliper work with new pads and discs to boost brake feel and controllability. The new 240mm rear brake rotor dissipates heat more efficiently, for more consistent performance under racing conditions.