Chassis / Suspension

• BILATERAL BEAM ALUMINUM FRAME: The YZ450F’s compact aluminum frame further refines the instinctive handling that makes this Yamaha one of the sharpest machines in its class. Every aspect has been carefully retuned, with thinner main spar construction, thicker down tubes, revised top triple clamp, and motor mounts that work together to optimize overall rigidity balance for excellent handling, especially in fast, bumpy conditions.
• COMPACT BODY AND SEAT DESIGN: The YZ450F features stylish bodywork from tip to tail, including a compact fuel tank specifically designed for motocross demands. The lower, forward-positioned handlebar position and the firmer seat assist the rider in keeping their weight forward during aggressive riding.
• REVISED CLASS-LEADING SUSPENSION: Industry-leading, fully adjustable KYB® coil spring-type fork with speed sensitive damping provides exceptional balance between handling and bump absorption. The linkage-type rear suspension features a KYB® shock with damping characteristics to match the YZ450F chassis.
• BRAKE SYSTEM: A large 270mm front disc brake is coupled with a rigid caliper and aggressive pad material that offers outstanding braking performance and machine control. Out back, the rear system sheds weight with a compact caliper and 240mm rear rotor for better heat dissipation.
• LIGHTWEIGHT WHEELS: Careful computer-aided refinement of each wheel’s cross-sectional profile shaves valuable weight without sacrificing durability.

Engine

• MORE COMPACT REARWARD-SLANTED CYLINDER: The YZ450F’s distinct rearward-slanted cylinder light and compact design are ideally positioned in the frame for optimized weight distribution. Inside, the head features steep valve angles to allow for an even straighter down-draft intake port, as well as more aggressive cam profiles and larger diameter exhaust header joint that work together with a higher compression bridge-box design piston, DLC-coated piston pin, and longer connecting rod to give YZ450F riders the best balance of class-leading power with an outstanding level of control.
• YAMAHA POWER TUNER APP: The free of charge and industry-exclusive Yamaha-created 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 FUEL 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.
• ELECTRIC STARTER SYSTEM: The YZ450F 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.
• LAUNCH CONTROL SYSTEM (LCS): LCS optimizes engine output for quicker, smoother race starts every time by boosting controllability out of the gate and ensuring the rider has the best chance to get the holeshot and lead the competition into the first turn.
• ADVANCED FUEL INJECTION: The engine breathes through a 44mm Mikuni® throttle body that is fed by a high pressure electric pump to ensure optimum fuel atomization and power for a wide range of riding conditions. The ultra-compact throttle body also saves weight for excellent mass-centralization.
• COOLING SYSTEM: The YZ450F features radiators that are angled directly in the incoming air stream for enhanced cooling, even under the most demanding race conditions.
• ROBUST TRANSMISSION AND CLUTCH: The YZ450F’s transmission gears use a wide surface area that is balanced against updated clutch components. All designed to boost durability, the shift drum and selectors improve feel with a shorter, more direct stroke when changing gears, too.
• WRAPAROUND REAR-POSITIONED EXHAUST: Yamaha's innovative exhaust pipe design enhances mass centralization by moving the rear end of the exhaust pipe farther forward and enabling the muffler's position closer to the machine's center of the mass. Thanks to a wider joint profile, power development is enhanced, too.

Other Features

• TRIPLE CLAMP WITH ADJUSTABLE HANDLEBAR MOUNTS: The top triple clamp design balances rigidity for improved steering feel while the 4-position adjustable handlebar clamp is rubber-mounted for comfort, reduced handlebar vibration and easily tunable bar position.
• EMBEDDED GRAPHICS: Yamaha’s unique embedded graphics are built into the bodywork for extended durability, resisting both peeling and damage.
• RACE-WINNING DETAILS: The YZ450F includes top-spec details, including 1-1/8” aluminum tapered handlebars, wider yet lighter foot pegs, a quick-adjust clutch perch, stylish blue rims and gold chain.

Top Features

• ULTIMATE OPEN CLASS YZ®: More Power. Better Handling. Simply put, the 2021 YZ450F™ is better everywhere. With a more compact motor, a thoroughly refined and balanced chassis and improved ergonomics, the YZ450F gives the rider the ability to perform at their best, lap after lap.
• 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 ultimate track-side tuning, or use the handlebar-mounted switch to change fueling maps on the fly.
• COMPACT AND CUTTING-EDGE FUEL-INJECTED ENGINE: Inside the ultra-compact motor, a high-compression cylinder head, forged piston, aggressive cam profiles and much more work together to give YZ450F riders the best balance of open-class power with controllability. Plus, the electric start makes it even easier.
• ADVANCED ALLOY FRAME: Yamaha’s bilateral beam aluminum frame features updated main spars, triple clamps and engine mounting points that centralize mass and provide an ideal rigidity balance between cornering feel and straight-line confidence.
• CLASS-LEADING SUSPENSION: Yamaha's spring-type forks with refined, speed-sensitive damping give industry-leading suspension performance straight out of the box.
• CYLINDER HEAD: The YZ450F's potent motor includes combustion chamber geometry with steeper valve angles, aggressive cam profiles, a high 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.
• SMOOTHER SHIFTING: Gear widths and shapes improve shifting feel and precision without sacrificing Yamaha's legendary reliability under racing conditions.
• BILATERAL BEAM FRAME: The YZ450F aluminum frame features 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 YZ450F takes rider confidence to new levels.
• BRAKING SYSTEMS: The rigid front caliper and compact rear caliper work with the pads and discs to boost brake feel and controllability while the 240mm rear brake rotor dissipates heat more efficiently for more consistent performance under racing conditions.
• SUSPENSION TUNING: The front and rear damping, tuned in concert with the chassis, 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.