Race-ready performance that hammers the competition

On the racing circuit, winners must constantly improve to remain on top. Kawasaki’s KX250F motocrosser is no exception. A leading performer in the 250 four-stroke ranks, the KX250F has successfully defended against challenges to its top spot for the last three years. However, there’s no resting on laurels in this group, not to mention the primary need of every racer on the starting line is a machine that can deliver wins yet remain highly reliable throughout the season.

Kawasaki engineers met the challenge and answered the call with the new 2009 KX250F. This world-beating racer has been thoroughly reinvented with a new slimmer look, lighter handling, better ergonomics and a host of changes that enhance engine performance and improve durability.
The 2009 KX250F features a cylinder head with a new intake port design that’s smoother, freer flowing, better sealed and holds new stronger titanium valves with a longer service life. New factory-level crankshaft balance and a tapered titanium exhaust pipe add up to smoother and more impressive power delivery from the 249cc, liquid-cooled, four-stroke engine.

A revised crank web significantly increases the crankshaft balance factor . The end result is reduced engine vibration, smoother power delivery and a noticeable improvement in low rpm throttle response. From the first crack of the throttle, to wide-open at the rev limiter; this new engine generates controllable, class-leading performance.
The KX250F’s engine cooling capacity was increased via a new water jacket routing for more effective flow and larger radiators with new louvers for enhanced thermal efficiency. Increased from three to four blades, the new louvers are smaller with a shallower angle to flow more air.
Engine oil volume was lowered to 1.3L to reduce weight and mechanical loss while a new KX450F type crankcase oil filter was added to maintain reliability. The transmission durability was boosted with a bigger interval between the gear shafts that allows the use of stronger gears, and there are new, stronger clutch and generator covers.
By switching to a new ratchet drive shift mechanism and integrating the clutch cable holder into the crankcase; Kawasaki’s engineers were able to deliver improved shifting and clutch lever feel from the new transmission. The lever ratios, spring rates and shaft locations were also revised.

Part of the KX250F’s slimmer feel is its new aluminum perimeter frame and sub-frame. A blend of forged, extruded and cast parts, the new frame uses fewer parts and gussets, is 2.2 lbs lighter than the 2008 model and is designed to provide enhanced stability with a better rigidity balance and improved drive from the rear tire. The main frame spars were reshaped and provide a 6mm narrower overall profile at the rider’s knees. A new manufacturing process and down tube design shed weight, and work in harmony with relocated engine mounts to improve rigidity balance.
Working in conjunction with the frame revisions is a new aluminum swingarm now pivoting from a higher position on the frame for improved traction. It is now a lighter, more tapered design with aVbCrLf profile and a new cross bracket. A longer rear suspension stroke, and thus more precise rear suspension tuning, was achieved by mounting the suspension arm of the Uni-Trak rear suspension system below the swingarm.
A new rear Showa shock with a large 50mm piston diameter has a revised layout and damping characteristics that offer better response, improved bottoming performance and ride feel. Also featuring a Kashima Coat on the shock internals, the rear shock settings should please riders.
With the chassis balance and suspension settings tuned to suit experienced racers, the KX250F offers a host of new features for better cornering and handling. Included in the Showa fork upgrades is a Lites-class first; titanium coated inner tubes. This dark navy blue coating not only decreases stiction, but also provides a super-hard surface to help prevent scratches and damage to the tubes. Further contributing to smooth suspension action; the inner surface of the outer fork tubes has a friction-reducing Kashima Coat treatment.
Optimized rigidity balance was achieved by reshaping and stiffening the upper triple clamp, as well as reshaping and decreasing the rigidity of the outer fork tubes. A 1mm reduction in fork off-set, revised suspension settings and enlarged, wrap around tube guards round out the fork enhancements.
Durability improvements were not limited to internal components on the new KX250F. Its larger, resin skid plate and narrower, longer lasting chain guide -both offering greater protection without higher weight- are examples of the race-oriented durability improvements that abound on the new KX250F. Part of the sleek new bodywork styling, the one-piece, dual injected, two-tone black and green plastic shrouds and side number plates translate into less time hassling with backgrounds and graphics and more time collecting trophies. Plus, the longer lasting finish, with fewer graphics to wear off, helps stretch racers dollars that much further.
In addition to giving the KX250F a stunning new look; the completely revised bodywork was designed with rider comfort and ergonomics in mind. Offering the rider an even slimmer interface with natural positioning makes it easier for racers to stay relaxed and in control. Ergonomic enhancements include improved feel from the wider 50mm foot pegs, a slimmer new seat design with firmer urethane foam, a non-slip top surface and smooth sides provides good seated grip and excellent rider mobility.
The rest of the KX250F is equally impressive, with premium-quality Renthal aluminum handlebars included as standard equipment along with black triple clamps, number plates, engine covers, hubs and wheels. Factory-style graphics finish off the package and compliment the KX250F’s stellar on-track performance.
Racers who ride their KX250F at designated events are eligible to receive support from Team Green’s amateur racing support program. Each year, Team Green provides regional support vehicles and highly trained technicians at more than 100 events, offering technical information and assistance to those who race Kawasaki products. Kawasaki also offers a comprehensive contingency program for amateur and professional riders who place well at designated events.
Kawasaki Motors Corp., U.S.A. (KMC) markets and distributes Kawasaki motorcycles, ATVs, personal watercraft, utility vehicles and recreation utility vehicles through a network of more than 1,500 independent retailers, with an additional 8,000 retailers specializing in Kawasaki power products and general purpose engines. KMC and its affiliates employ nearly 3,650 people in the United States, with 430 of them located at KMC’s Irvine, California headquarters.
Kawasaki affiliates can be found on the Internet at www.kawasaki.com.