- Liquid-cooled, four-stroke single, DOHC, four valves per cylinder
- 449 L
New 2008 KFX450R introduces ATV community to Kawasaki racing technology.
Motocross performance based on the World Champion KX450F.
Take the short cut to the circuit with the all-new Kawasaki KFX®450R ATV. This high performance machine doesn’t require extensive and expensive modifications to make it race-ready, because it already includes all the race-winning performance and technology required for success straight out of the crate.
The KFX450R’s design incorporates everything riders need to win races. Every component was chosen to maximize performance on the track or in the woods and to minimize the fuss of getting there. This highly advanced racing ATV comes with all the performance and technology necessary to put riders at the head of the pack.
The KFX450R ATV uses a powerplant based on Kawasaki’s highly acclaimed KX450F motocross engine. With the addition of an efficient and highly-responsive 32-bit digital fuel injection system, the KFX450R’s engine produces more torque in the low and medium rpm ranges for outstanding hole-shot acceleration. The use of fuel injection helps ensure that the engine’s performance remains consistent and is virtually unaffected by changes in temperature or altitude. This ATV’s ability to find traction is superb, and its four-stroke torque helps keep the wheels hooked-up for improved handling and higher corner speeds. Other race-ready features include a lightweight titanium exhaust header pipe and a durable forged piston.
Winning at the track depends on a chassis that’s built to handle tough race conditions. The KFX450R offers the full benefits of an all-aluminium frame, combining exceptionally light weight with the extreme stiffness needed to win races. However, it isn’t just advanced materials that give the KFX450R its race-winning edge. The front suspension design incorporates extremely long lower A-arms mounted to a single box-section lower frame tube. This results in outstanding response from the front-end. At the rear is a cast aluminium swingarm that provides the ideal balance of flexibility and rigidity resulting in unparalleled traction. The high-tech chassis also features a very low center of gravity and excellent roll resistance. Regardless of changing conditions or rough track surfaces, this race-oriented chassis makes the KFX450R a potent weapon in the battle for ATV supremacy.
Competition-oriented equipment, including the only reverse gear in its class, helps keep the KFX fast and reliable. Previously unheard of in racing, the KFX 450R’s lightweight reverse system lets riders quickly extricate themselves from first turn chaos or dead-end trails. This important feature means on-track incidents (like getting nosed-into a wall) no longer result in an early retirement from the race.
Kawasaki has also made the KFX450R easy to work on, so riders can concentrate on winning instead of wrenching. The two-piece front and rear “lapped” fenders make it possible to replace sections separately if they get damaged. Even the headlight assembly is quickly detachable for closed-course races, and the compact design means that the ATV looks just as aggressive with or without headlights. These features leave little doubt that the new KFX450R was designed to get its rider on the racetrack and winning races as quickly as possible.
449cc liquid-cooled, DOHC, four-valve, four-stroke single
Based on the engine from the World Championship winning KX450F
A lightweight forged piston reduces reciprocating weight
Triple piston rings and a 21mm diameter piston pin help increase durability and reduce necessary maintenance
The intake ports feature a special coating. The extremely smooth surfaces improve intake efficiency at all rpm
Lightweight titanium valves and aluminum valve spring retainers reduce reciprocating weight and boost high-rpm reliability
Lightweight high-performance titanium exhaust header contributes to low and mid-range throttle response
Electric starting facilitates quicker stall recovery and lowers rider fatigue
Large-volume airbox contributes to both intake efficiency and the sharp engine response. An air duct fashioned from polyethylene (known for its ability to resist deformation caused by intake pulses) helps ensure stable engine performance
Torque delivery is tuned to match the rear tires’ ability to deliver traction, making it easier to accelerate without excessive wheelspin. Efforts were made to achieve the widest possible torque curve, so that traction can be maximised through a greater part of the rev range
Asymmetrical high-acceleration cams yield high intake efficiency
Digital Fuel Injection
32-bit digital fuel injection system uses a 42mm throttle body. This system measures coolant temperature, air intake temperature, air intake pressure, engine speed and throttle position, then automatically delivers the ideal amount of fuel to optimize power delivery
Crisp engine response is especially advantageous for instant acceleration after landing jumps
Fuel injection also provides trouble-free starting – a great benefit in races where riders line up with their engines off and need to start their engines before being able to blast away from the starting line
Fuel injection allows the use of a lighter throttle return spring. This helps reduce rider fatigue, because less pressure is required at the throttle lever
The five-speed (one-down, four-up) manual transmission locates the reverse gear below first. Actuating the reverse-lock release lever when in first gear allows you to shift “down” into reverse
Compact reverse-lock release lever can be activated with the right thumb, allowing the reverse gear to be engaged while still keeping the front brake lever depressed
The combined weight of the reverse gear system and the lightweight aluminium chassis is no heavier than using a steel frame without reverse
Highly rigid aluminum frame contributes to the KFX’s excellent handling and traction. The frame’s high torsional rigidity enhances stability in corners and allows the suspension to be easily set up to suit course conditions
Designed for high corner speeds, the KFX ATV sits low to the ground, helping to reduce roll tendencies
Mounting the battery and coolant tank in front of the engine lowers the center of gravity, and helps weight the front wheels for increased traction when cornering
Single box-tube lower frame contains the front A-arm attachment points. This design is narrower than the competition’s frames and enables the use of longer lower A-arms
Advanced Suspension Design
Positive and negative suspension travel enhances the front wheels’ ability to stay in constant contact with the ground. This helps maintain traction and steering authority during hard acceleration and in situations where the ground drops away
Dual-rate front springs help deliver progressive suspension travel to provide excellent rough-surface handling
Extra-long lower front A-arms help minimize camber variations through the suspension stroke, to maximize front wheel traction and boost stability
Motocross style rear shock features both high and low-speed compression adjustability as well as adjustable rebound damping
Cast aluminum rear swingarm features curved lines and rounded edges to help disperse stress, as well as different wall thickness for each surface, resulting in a design that is both light and strong
The swingarm’s high torsional rigidity contributes to excellent rear wheel traction
The rear axle is tapered for reduced unsprung weight
Front and Rear Disc Brakes
Dual front hydraulic disc brakes offer consistently strong stopping performance
Petal-type rear brake rotor reduces unsprung weight and helps clean the brake pads for more efficient braking performance in difficult conditions
Integrated rear parking brake is designed to be easily engaged and released while wearing gloves. When engaged, the parking brake lever also prevents the clutch lever from being actuated
Two-tone seat features a smooth top surface for excellent rider mobility and slip-resistant sides for good grip when hanging off in corners
Seat, tank and side covers are shaped to allow excellent rider mobility and to provide support when hanging off in corners.
Tapered Renthal Fatbar offers both strength and light weight
Handlebar mount designed to accommodate other MX-type handlebars, enabling riders to select from numerous after-market styles
Specially designed rear wheels feature reinforcing plates for the rims. Located on the axle side of the rims, these plates reinforce the rims where strength is most needed while minimizing weight
Wide front bumper, can be gripped with two hands to push/pull the ATV
Two-piece “lapped” front and rear fenders can be replaced separately in the event they are damaged
Detachable front headlight assembly can easily be removed to reduce weight when racing
Optional kick-start system is available for MX-style (GNC) races where light weight is a priority
Engine: Liquid-cooled, four-stroke single, DOHC, four valves per cylinder
Bore x stroke: 96 x 62.1mm
Fuel Injection: 32-bit digital, with 42mm Keihin throttle body
Ignition: Digital AC-CDI
Transmission: Five-speed with reverse
Final drive: Two-wheel drive, chain
Frame type: Aluminum double cradle, racing type
Front suspension / wheel travel: Dual A-arms, coil-over shocks / 8.5 in
Rear suspension / wheel travel: Swingarm with piggy-back reservoir shock, dual-rate spring / 10.0 in
Front tires: AT21x7-10
Rear tires: AT20x10-9
Front brakes: Dual 163mm discs with two-piston calipers
Rear brake: 200mm petal-type rotor with single-piston caliper
Overall length: 71.1 in
Overall width: 46.0 in
Overall height: 41.9 in
Seat height: 30.9 in
Wheelbase: 49.4 in
Ground clearance: 4.3 in
Lighting: Dual removable headlights
Dry weight: 364 lb
Fuel capacity: 2.6 gal
Footpegs: Sport-style serrated
Color choices: Lime Green / Super Black, Bright White / Super Black, Super Black
An all-aluminum chassis weighs in at only 26 lbs. Kawasaki borrowed this technology straight from the ATV racing aftermarket industry. The set up allows for better steering and offers more shock travel as well.
The KFX450R starts with ease. It is a bit strange to hear a electronic fuel injection pump working when you turn the key on. There is no choke, but there is a idle adjusting knob that is pulled for cold starting.
The parking brake is super easy to use, and actually works. Just flip the lever on or off. When the brake is on, the clutch will not depress.
The KFX450R is one sharp looking machine. The headlight assembly, as well as the front fenders, are quickly detachable. The two-piece front and rear “lapped” fenders make it possible to replace sections separately if they get damaged or if you just want to go without them.
A reverse gear on a race quad? "Why not," says Kawasaki. The reverse lever is near the thumb throttle for quick engagements in hurry-up situations. Clutch in. Select 1st gear. Push the reverse lockout lever, then push the gear selector down one more click. Red light comes on and you are in reverse. When you are done, click the gear selector up to 1st again. Simple.