Engineered by Yamaha for the cross - motocross motorcycle segment, the 2009 Yamaha YZ450F pairs a 449 cc (27.4 cu in) liquid-cooled single cylinder, four-stroke architecture with road-focused gearing. Internal engine geometry specifies a bore and stroke of 95.0 x 63.4 mm (3.7 x 2.5 inches) with a 12.3:1 compression ratio.
On the scales, the YZ450F measures 108 kg (238 lbs) wet (curb). Rider ergonomics and chassis geometry center around a 988 mm (38.9 in) seat height — reflecting a long-travel chassis stance that favors ground clearance and off-pavement control, combined with a 1,494 mm (58.8 in) wheelbase engineered for balanced agility and highway composure. The 6.81-liter (1.8 US gal) fuel tank supports practical everyday commuting and weekend road stints.
Within MotoLibrary's Yamaha archive, this model family spans 19 indexed model years from 2008 to 2026, allowing buyers to track year-over-year changes in emissions tuning, weight and equipment.
Standover Height
988 mm (38.9 in)
Engine
Displacement449.0 ccm (27.40 cubic inches)
Engine TypeSingle cylinder, four-stroke
Engine DetailsSingle cylinder, four-stroke
Compression12.3:1
Bore x Stroke95.0 x 63.4 mm (3.7 x 2.5 inches)
Valves/Cylinder5
Fuel SystemCarburettor. Keihin FCR MX39
Fuel ControlDouble Overhead Cams/Twin Cam (DOHC)
IgnitionCDI
CoolingLiquid
Transmission
Gearbox5-speed
Final DriveChain (final drive)
Chassis
Front SuspensionSpeed-Sensitive System inverted fork
Front Travel300 mm (11.8 inches)
Rear SuspensionFully adjustable single shock
Rear Travel312 mm (12.3 inches)
Wheelbase1494 mm (58.8 inches)
Ground Clearance373 mm (14.7 inches)
Wheels & Brakes
Front Tyre80/80-21
Rear Tyre120/80-19
Front BrakesSingle disc
Front Brake Ø245 mm (9.6 inches)
Rear BrakesSingle disc
Rear Brake Ø245 mm (9.6 inches)
Dimensions & Weight
Weight incl.108.0 kg (238.0 pounds)
Seat Height988 mm (38.9 inches) If adjustable, lowest setting.
Use this page to compare this motorcycle by its real specifications, not only by model name. Focus on the details that affect fit, comfort, handling, range and ownership.
Seat Height
Check the seat height against your inseam and riding posture before choosing a motorcycle.
Fuel Capacity
Fuel capacity helps estimate touring range and how often you may need to stop.
Brakes
Brake setup is worth comparing if you ride in traffic, mountains or with a passenger.
Suspension
Suspension details can matter for comfort, road feel and long-distance riding.
Transmission
Transmission and final drive affect maintenance, smoothness and everyday usability.
