2018 Yamaha YZ450FX


2018 Yamaha YZ450FX


Designed for closed course X-Country and enduro-type racing the YZ450FX combines light, nimble handling with the power of a 450.

Additional Features

  • GYTR® POWER TUNER READY: Accessory GYTR Power Tuner lets owners adjust air/fuel mixture and ignition timing maps to match engine performance characteristics to the rider and race conditions in a matter of seconds with the push of a few buttons.
  • REAL WORLD TOUGH FEATURES: Rugged plastic skid plate, quick-adjust clutch, aluminum handlebars and a side stand are standard for added rider convenience.
  • SIMPLIFIED SERVICING: Redesigned air cleaner cover provides tool-less access to the air filter, positioned at the front of the bike to avoid roost from the rear wheel. A high-quality sealed O-ring chain is tough and durable.
  • EMBEDDED GRAPHICS: Yamaha’s unique embedded graphics are built into the bodywork for extended durability, resisting both peeling and damage.

Chassis / Suspension

  • BILATERAL BEAM ALUMINUM FRAME: YZ450F-based frame offers a compact size while optimizing mass centralization. With its extensively tested assembly of aluminum forgings and extrusions complete with model-specific engine mounting, the FX frame retains legendary Yamaha handling and response.
  • ADVANCED YZ450F FRONT FORK: Fully adjustable YZ450F-based KYB® spring-type fork with speed sensitive damping delivers precise, fade-free handling.
  • CROSS COUNTRY SHOCK: The rear linkage and KYB® shock provides 11.6 inches of travel with adjusters for high- and low-speed compression damping, rebound and spring preload—and features a large piggyback reservoir for excellent damping and fade resistance.
  • 270MM FRONT BRAKE: 270 mm front brake system provides exceptional stopping power and braking control.
  • GNCC®-SPECIFIC TIRES AND WHEELS: Lightweight 21-inch front and 18-inch rear rims provide exceptional durability with enduro-specific tires.


  • CROSS COUNTRY-TUNED YZ450F POWER: YZ450F-style 449cc liquid-cooled DOHC four-stroke, with forward-positioned straight intake, delivers massive power specifically tuned for cross country racing, to challenge for race victories in the very competitive GNCC® and Hare Scrambles race series.
  • INNOVATIVE ENGINE DESIGN: The position of the engine moves the rotational mass of the cams towards the center of the bike which allows for a straight shot, down-draft intake and straight exhaust port for ultimate performance. This also keeps the airbox up high, out of dust and mud/water.
  • WRAPAROUND REAR POSITIONED EXHAUST LAYOUT: Lightweight YZ450F-spec exhaust system maximizes engine power while centralizing mass, thanks to the innovative wrap-around header design.
  • ADVANCED FUEL INJECTION: The fuel injection system uses 3D mapped electronic control for the fuel and ignition timing that are optimized for cross-country racing, with a YZ450F-based 44mm throttle body.
  • WIDE RATIO GEARING: A five-speed wide-ratio transmission is used to insure the right gear is selected for a wide variety of terrain found in cross country racing, from tight single tracks to wide-open desert blasts.
  • FX-SPECIFIC CLUTCH SYSTEM: Based on the YZ450F, the clutch plate material, springs, push lever and oil valve are optimized for cross-country racing.
  • YZ-F-DERIVED COOLING SYSTEM: Large-capacity YZ450F radiators provide maximum cooling efficiency with great strength, and can be fitted with an accessory cooling fan for additional airflow at slower speeds.
  • ELECTRIC STARTER SYSTEM: Push button electric start makes starting the YZ450FX easy and convenient, complete with a simplified electrical system.

Top Features

  • INNOVATIVE HARE SCRAMBLE/GNCC® ENGINE DESIGN: The YZ450FX™ shares the revolutionary rearward-slanted-cylinder design of the YZ450F™ that allows for a straight downdraft intake with a symmetrical port layout. In the YZ450FX, this engine delivers a controllable, torquey power character with strong top-end power tuned specifically for cross-country racing.
  • BILATERAL BEAM ALUMINUM FRAME: A nearly identical bilateral beam frame that is found on the championship winning YZ450F is used on the YZ450FX. It places the engine, fuel tank and exhaust close to the center mass of the bike for extremely light and nimble handling character.
  • ADVANCED FUEL INJECTION: The YZ450F-based Keihin® 44mm throttle body fuel injection system is tuned for cross-country racing and ensures smooth throttle response and easy starting in nearly all conditions.
  • CROSS COUNTRY-SPECIFIC SUSPENSION: Industry-leading, YZ450F-derived KYB® spring-type forks with speed sensitive damping and a linkage-type, KYB® rear shock both feature fully adjustable settings designed specifically for cross country racing.
  • CROSS COUNTRY PODIUM READY: With a two gallon fuel tank, sealed O-ring chain, and an 18-inch rear wheel with XC racing tires, the YZ450FX is ready to win right out of the box.
  • ELECTRIC STARTER SYSTEM: The YZ450FX features an electric starter to help reduce rider fatigue along with a new main switch-free electrical system for easier starting off.

General Information

Manufacturer Yamaha
Model Year 2018
Model YZ450FX
Model Code YZ450FXJ
Stock Number C4309
Color Team Yamaha Blue



Front - 270 mm hydraulic single disc

Rear - 245 mm hydraulic disc


Front - 90/90-21 Dunlop® AT81F

Rear - 120/90-18 Dunlop® AT81


Length 85.2 in.
Height 50.4 in.
Width 32.5 in.
Weight Wet - 262 lb.
Ground Clearance 12.8 in.
Wheelbase 57.7 in.
Seat Height 38 in.


Transmission Wide-ratio constant-mesh 5-speed
Final Drive O-ring chain


Engine DOHC, 4-stroke, 4 titanium valves
Displacement 449 cc
Bore x Stroke 97 x 60.8 mm
Compression Ratio 12:5.1
Fuel System Keihin® fuel injection, 44 mm
Fuel Capacity 2 gal.
Ignition TCI (Transistor Controlled Ignition)
Clutch Multi-plate wet
Cooling Liquid



Front - KYB® spring-type fork with speed sensitive damping, fully adjustable; 12.2 in. wheel travel

Rear - KYB® single shock, fully adjustable; 12.5 in. wheel travel

Rake 26.3°
Trail 4.5 in.


Warranty 30 Day (Limited Factory Warranty)