2009 YZ250F motorcycle

Key Features:

    * Ongoing refinement to chassis produce an amazingly balanced, light-handling machine with performance that's accessible to all levels of riders.
    * Five-titanium-valve engine with 13.5:1 compression ratio spins out great torque and horsepower.
    * A carefully tuned aluminum frame made up of forgings, weldings, castings and tubing means sharp, super-precise handling.
    * Mass centralization provides fantastic overall balance and performance.
    * A ProTaper? aluminum handlebar in adjustable clamps and Excel rims are just a few tricks up the YZ250F's sleeve.
    * Dry sump lubrication system circulates more oil for the best durability in motocross

 New for 2009:

    * Redesigned exhaust system has a 60mm longer titanium header for better low-end grunt plus a 50mm shorter aluminum silencer for optimum low-rpm throttle response.
    * Both carburetor jetting and CDI ignition mapping settings are precisely reworked to deliver increased engine performance with new exhaust.
    * New clutch eliminates the judder spring and uses a floating rubber damper instead of a coil spring to provide unmatched clutch performance.
    * New clutch eliminates the judder spring and uses a floating rubber damper instead of a coil spring to provide unmatched clutch performance.
    * Newly designed swingarm is lighter and helps to achieve excellent rigidity balance for superb cornering and rear wheel traction.
    * Lightweight suspension linkage is redesigned to match the new swingarm.
    * New rear wheel hub is lighter and designed for the larger 25mm diameter axle (up from 22mm), helping to achieve the overall rigidity balance of rear suspension components.
    * New clutch lever is shorter, stronger, and lighter, with a lever position adjuster to accommodate different riders. Quick adjuster makes maintenance easy.
    * Front brake hose clamp is now aluminum, greatly reducing its weight.
    * New seat cover has great grip and more durability, and it's easy to clean.
    * Premium drive chain has gold colored plates for outstanding looks.

 Engine:

    * Liquid-cooled 250cc, five-titanium-valved, DOHC, four-stroke is powerful and highly tractable, with an rpm redline for competition-crushing pulling power.
    * 37mm Keihin? FCR flat-slide carburetor with throttle position sensor (TPS) ensures precise fuel/air mixing and lightning-quick throttle response.
    * Cylinder body and crankcase feature a large cutaway section to reduce pumping loss and increase midrange performance.
    * Primary kickstarting (with automatic decompression and convenient handlebar-mounted hot start lever) ensures easy restarts.
    * Slick, five-speed transmission with heavy-duty, multiplate clutch features an involute spline setup, ensuring smooth shifting and instant hookup under power.
    * Magnesium cylinder head cover - now covered matte black - helps shave weight.
    * Trick, works-style clutch lever features race-spec barrel adjuster for on-the-fly adjustability.

 Chassis/Suspension:

    * Extensively tested aluminum frame uses a mix of alloy castings, forgings and extrusions to produce a tuned-flex frame that makes the YZ250F the best-handling bike in its class.
    * Speed-Sensitive System 48mm KYB? fork damping force is controlled by piston speed: provides a smoother, more precise ride.
    * Four-way adjustable, rear shock with Kashima-coated internals reduces friction for fantastic compliance and great handling.
    * Removable aluminum rear subframe is constructed of square-section tubing for light weight and easy maintenance.
    * Lightweight front wheel hub for reduced unsprung weight and increased durability.
    * Lightweight front and rear brake calipers with aluminum pistons and anti-bubble front master cylinder; wave-style rotors reduce unsprung weight and deliver strong stopping power.
    * Lightweight 21-inch front and 19-inch rear Excel rims are exceptionally durable and reduce unsprung weight.

Engine
Type    250cc liquid-cooled DOHC 4-stroke; 5 titanium valves
Bore x Stroke    77.0mm x 53.6mm
Compression Ratio    13.5:1
Carburetion    Keihin FCR MX37
Ignition    CDI
Transmission    Constant-mesh 5-speed; multiplate wet clutch
Final Drive    Chain Drive
Chassis
Suspension/Front    Speed-Sensitive System inverted fork; fully adjustable, 11.8-in travel
Suspension/Rear    Fully adjustable single shock; 12.0-in travel
Brakes/Front    Hydraulic single disc brake, 250mm
Brakes/Rear    Hydraulic single disc brake, 245mm
Tires/Front    80/100-21 Bridgestone? 403
Tires/Rear    110/90-19 Bridgestone? 404
Dimensions
Length    85.1 in
Width    32.5 in
Height    51.2 in
Seat Height    38.8 in
Wheelbase    57.8 in
Ground Clearance    14.6 in
Wet Weight    226 lb
Fuel Capacity    1.8 gal

Liquid-cooled 250cc, five-titanium-valved, DOHC, four-stroke