THE BIKE THAT BUILDS CHAMPIONS One owner. These options: FMF slip on, frame guards, hand guards and radiator braces. Clean bike, ready to ride.
With more Supercross and Motocross championships than any other manufacturer, the KX™ name is synonymous with winning. The KX™450 motorcycle represents the flagship of the KX lineup, built with the sole purpose of dominating the track. Over the past four decades, we've learned what it takes to win and stay on top. Our dedication to building the ultimate machine is undeniable, and the KX™450 represents this to the fullest
2021 Kawasaki KX 450
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Chassis & Ergonomics
- MADE TO SHAVE LAP TIMES: Experience the race-winning advantage of a strong and lightweight chassis, agile handling, and exclusive ERGO-FIT® technology.
- BALANCE MEETS PRECISION: A lightweight aluminum perimeter frame and swingarm provide overall rigidity balance, contributing to precise cornering. Front-end feel is predictable and maximum traction is gained at the rear wheel.
- GET A GRIP: Wide footpegs ensure excellent grip for optimum comfort and control, and make it easier to weight the pegs.
- PERFECT FIT: Find your best performance with the Kawasaki ERGO-FIT® advantage. Four handlebar positions and two footpeg positions allow you to tailor the KX™450 motorcycle to your body size, riding style and preference.
- NEW RENTHAL® FATBAR® HANDLEBAR: A factory-style aluminum Renthal® Fatbar® handlebar comes standard, offering reduced vibration. With grips positioned lower and closer to the body, riders can shift weight forward more easily to improve front wheel traction, and increase front traction feel, to ride more confidently at the limit.
Next-Level Technology
- RIDE WITH CONFIDENCE: From quick, reliable starting to advanced braking power, the KX™450 motorcycle offers superior features designed to inspire confidence. What's more, this race-ready machine is backed by decades of championship-proven experience.
- ADVANCED STOPPING POWER: Next-level stopping power matches incredible acceleration capability. Up front, an oversized 270mm Braking® petal disc with dual-piston caliper offers sharp response and a strong, consistent feel. In the rear, a large-diameter 250mm Braking® petal disc complements the front for race-ready performance.
- RELIABLE STARTING: Being able to restart your engine quickly after a stall can make or break a race. Powered by a compact and lightweight Li-ion battery and supported by an automatic centrifugal decompression system, all it takes is the push of a button to start up
- LIGHT PULL & SELF-ADJUSTING: A new coned disc-spring hydraulic clutch offers lighter clutch pull and a wider engagement range. Larger diameter plates provide increased fade resistance.
Power & Performance
- BUILT TO WIN: The 2021 KX™450 engine offers increased performance and delivers broad, useable torque and strong, responsive power across the rev range. From the starting gate to the finish line, this race-ready machine is built to stay ahead of the pack.
- POWER THROUGH THE FINISH: The powerful 449cc engine features new friction reduction coating on the piston for increased engine performance.
- EVERY SECOND COUNTS: A factory-style launch control system helps put the bike’s power to the ground for maximum acceleration at the start of the race, making the holeshot yours for the taking.
- PULL AHEAD: A flat torque curve makes it easier to get on the gas sooner, delivering smooth and powerful acceleration to pass the competition and keep you ahead of the pack.
- FINELY TUNED POWER: Use the DFI® couplers to choose engine settings to suit your riding style or track conditions. This plug-and-play style system allows quick and easy selection from three pre-programmed fuel injection and ignition mapping settings. Fine tune your ECU setting with factory precision. The KX™ FI Calibration Kit* features a handheld controller that enables adjustment of fuel mapping and allows storage of presets without a PC. *Sold separately as a Kawasaki Genuine Accessory
Race-Ready Suspension
- LEAVE THEM IN THE DUST: Take the lead with proven race-winning performance. The highly adjustable suspension package delivers smooth action, firm damping and contributes to optimal traction.
- RACE READY: The 49mm Showa Coil Spring Front Fork combined with A-KIT Technology deliver excellent handling. Large-diameter inner tubes allow the use of large damping pistons for race-winning performance while a large-diameter front axle provides exceptional front-wheel traction.
- CHAMPIONSHIP PROVEN: The Uni-Trak® rear suspension system features adjustable dual-range (high- and low-speed) compression damping, adjustable rebound damping, and adjustable preload. The result is optimal damping and rear-wheel traction.
General Information
Brakes/Wheels/Tires
Brakes
Front - Single semi-floating 270 mm Braking® petal disc with dual-piston caliper
Rear - Single 250 mm Braking® petal disc with single-piston caliper
Tires
Front - 80 / 100-21
Rear - 120 / 80-19
Dimensions
Height
Overall - 49.8 in.
Weight
Curb without fuel- 232.7 lb.
Curb - 242.9 lb.** (Curb weight includes all necessary materials and fluids to operate correctly, full tank of fuel (more than 90 percent capacity) and tool kit (if supplied))
Ground Clearance
13.4 in.
Drivetrain
Transmission
5-speed, return shift, with wet multi-disc manual clutch and hydraulic clutch actuation
Engine
Engine
4-stroke single, DOHC
Bore x Stroke
96 x 62.1 mm
Fuel System
DFI® with 44 mm Keihin throttle body
Operational
Front Suspension
49 mm inverted telescopic coil-spring fork with 16-way compression damping and 16-way rebound damping
Travel - 12 in.
Rear Suspension
Uni-Trak® gas charged shock with piggyback reservoir with dual-range (4 turns stepless high speed / 19-way low-speed) compression damping, 22-way rebound damping and adjustable preload
Travel - 12.1 in.
Yamaha ATV Disclaimer
ATVs are recommended for those aged 16 years and older. YAMAHA recommends an approved training course. See your dealer or call
Yamaha SXS Disclaimer
Professional driver on closed course. Always protect the environment and wear your seat belt, helmet, eye protection and protective clothing. Read the owner’s manual and product warning labels before operation. Model shown with optional accessories. Vehicle specifications subject to change.
Yamaha Motorcycle Disclaimer
Professional rider(s) on closed area. Dress properly for your ride with a helmet, eye protection, and protective riding gear. Do not drink and ride. It is illegal and dangerous. Specifications are subject to change.