Yamaha WR450F Dirt Bike & Parts

New Yamaha WR450F in 2005
Frame height is reduced by 10mm, and seat height is a full 20mm lower, for lowered center of gravity, improved handling, and easier access for shorter riders on this Yamaha model.
Slimmer shrouds, seat, and fuel tank increase rider mobility on the bike, for great maneuverability and handling.
New, fully adjustable 48mm front fork tubes for excellent handling and comfort, along with new leg protectors for more coverage.
New carburetor and ignition settings deliver even more broad-band power, and a new air injection system (AIS) on California models makes them green sticker ready.
Renthal aluminum handlebar shaves weight and increases comfort.
New, shorter front brake hose routing provides excellent feel at the lever and eases brake maintenance.
Yamaha redesigned the clutch lever shape and clutch cable mean light clutch pull and less fatigue.
New front wheel collar makes front wheel removal quick and easy.
New aluminum muffler shaves weight, as does the new rear sprocket.
New left side cover now has a grab handle for convenience.

Engine:
The industry’s most powerful and most advanced four-stroke Enduro machine features electric starting.
Liquid-cooled, 449cc, 5-valve, DOHC, four-stroke with titanium valves features 63.4mm stroke delivering flat, broad torque (for instant hook-up) with high over-rev capacity and crisp, linear throttle response.
Titanium valves and load-reduced springs are super light, reducing reciprocating mass for fast-revving, hard-hitting power delivery across the rev range.
Yamaha 's Lightweight crankshaft helps decrease inertial mass reducing friction for fast-revving low-rpm response.
39mm Keihin FCR flat-slide carburetor with throttle position sensor (TPS) ensures ultra-precise fuel/air mixing and lightning-quick throttle response.
Digital CD ignition system delivers more precise spark and monitors engine speed to ensure optimal timing for faster, stronger response during hard acceleration.
Large-capacity radiator and louvers ensures maximum cooling efficiency.
Slick-shifting, wide-ratio, 5-speed transmission with Yamaha WR450F-spec, multi-plate clutch geared specially for quick-hitting power in woods and hard-pulling top-end on wide-open trails.
Lightweight exhaust system maximizes engine power and allows hassle-free replacement of oil filter.
Aluminum muffler with USFS-approved spark arrestor looks trick and keeps things light.
Trick, works-style clutch lever features oversize barrel adjuster for easy, on-the-fly adjustability of lever/cable play.
Automatic decompression system and convenient handlebar-mounted hot start lever ensures easy restarts.

Chassis/Suspension:
A Super-strong Yamaha twin-spar frame is lightweight and laterally rigid for minimal flex and razor-sharp handling.
Tapered swingarm is lightweight and rigid for compliant rear suspension action.
Removable aluminum rear subframe constructed of square-section pipe for reduced weight.
Rear suspension system features fully adjustable Kayaba shock with 12.0 inches of travel and separate adjusters for high- and low-speed compression damping.
Lightweight, removable aluminum rear subframe allows easy maintenance.
Lightweight 21-inch front and 18-inch rear Excel rims provide exceptional durability and help reduce unsprung weight for optimal suspension performance.
Premium Dunlop 739 knobbies offer unbeatable, competition-spec traction and excellent wear.

Additional YAMAHA Dirt Bike Features:
More weight savings come via, two-piece (part aluminum, part plastic) engine protector plates and thinner-walled engine guard construction.
Enduro-legal lighting front and rear increases versatility by maximizing nighttime and low-light visibility.
Large, 2.1-gallon fuel tank ensures excellent range.
Resettable tripmeter allows rider to keep track of both mileage and fuel reserves.
Adjustable front brake lever.
Cleated rear brake lever and folding shift lever tip offer superb grip and excellent durability.
Stylish Team Yamaha-inspired two-tone (black/blue) seat.
Repackable exhaust silencer.