2006 Kawasaki KX Motocross Models
KX450F | KX250F | KX250
2007 KX model pageKX450F | KX250F | KX250
2006 KAWASAKI KX 450F UNVEILED
Flagship KX combines huge 4-stroke power, 4-speed transmission, and twin-spar aluminum frame
Kawasaki, the brand that introduced the motocross world to perimeter frames, has unveiled an all-new flagship in its leading-edge KX™ motorcycle line. Every aspect of the 2006 KX450F, from its ultra-powerful four-stroke engine to the trick aluminum frame and suspension, reflects its purpose as a championship-winning race bike. Kawasaki engineers stressed every detail on the new, liquid-cooled, 449cc four-stroke engine to ensure that its provides maximum power and traction. Featuring double overhead cams, four valves and a Keihin FCR40 carburetor, it dishes out serious acceleration with smooth over-rev capability so the rider can use very ounce of its incredible power on the racetrack. Hand-finished intake ports maximize intake efficiency, while lightweight titanium valves and aluminum valve retainers reduce reciprocating weight for reliable valve control at high rpm. Plus, double valve springs provide stable operation under intense racing conditions. To ensure quick and easy starting, the KX450F features both an automatic compression release and hot start system. The KX450F utilizes newly designed, high-capacity Denso radiators, which provide superior cooling under racing conditions. With its tightly packed radiator cores and new fin design, the new radiators improve heat dispersion for consistent engine power characteristics and dependability.The KX450F comes equipped with a tapered titanium exhaust pipe that expands in diameter from 38 to 41mm, contributing to its broad powerband, and the silencer features new, long-fiber packing. Kawasaki engineers have matched the high-tech engine to a new four-speed transmission. Combined with a manual, multi-disc wet clutch, the four-speed transmission enables the rider to take advantage of the engine’s inherently broad powerband on the racetrack; from accelerating out of turns to high-speed straights, the rider can use the KX450F’s precise throttle control to adjust speed nearly instantaneously. And to protect the underside of the engine and transmission, the KX450F comes with a lightweight aluminum skid place. The KX450F chassis has been designed to help the rider put the engine’s power to the ground. To do this, Kawasaki engineers combined their experience designing steel perimeter KX frames and techniques used to construct the Ninja® ZX™-10R sport bike chassis to create an all new aluminum perimeter frame. Comprised of forged, extruded and cast aluminum parts, the strong twin-spar design gives the KX450F optimum balance of torsional and longitudinal rigidity. The frame was designed so that the center of gravity and key chassis dimensions would work together to enhance the rear tire’s ability to drive the KX450F forward instead of squatting under acceleration. Additionally, the four-stroke engine sits in an upright position within the new frame to further aid overall traction. Kawasaki then added complementary front and rear suspension to the KX450F. A Kayaba AOS (Air-Oil-Separate) fork keeps oil and air in separate chambers for stable damping performance during long motos. On the rear, the UNI-TRAK® rear suspension system features an alloy
swingarm with tapered spars and linkage ratios to maximize traction under acceleration. Front and rear petal disc brakes provide stopping power for the KX450F. This design not only helps to reduce unsprung weight, but the petal shape of the discs helps to clean the brake pads for more efficient braking performance. The slim profile of the KX450F frame, two-piece radiator shrouds that leave the upper frame spars exposed, and careful design of the remaining bodywork make the KX450F feel light and narrow beneath the rider. The KX450F comes with a Renthal aluminum handlebar, while the seat uses a slip resistant top surface for good grip when seated and smooth sides for enhanced rider mobility. The KX450F also features titanium footpegs and footpeg brackets for reduced overall weight. Complementing the KX450F’s ultra-high-performance design is aggressive bodywork and graphics. Kawasaki offers a number of optional parts for the KX450F, including a top mounting clamp for an oversized handlebar, aluminum and steel rear sprockets, solid petal disc brake rotors for wet racing conditions, optional springs for the front fork and rear shock, and a 20-inch front wheel.
FEATURES
Engine
449cc liquid-cooled, four-stroke single
Wide powerband extends into the over-rev
Top End
High-acceleration cams help the engine rev more quickly
Camshaft lobes and tappets feature soft-nitriding surface treatment for long wear and high-rpm reliability
Hand-finished surfaces of the polished intake ports improve intake efficiency at all rpm
Lightweight titanium 36mm intake and 31mm exhaust valves and aluminum valve retainers reduce reciprocating weight for reliable valve control at high rpm
Double valve springs help ensure stable valve operation
Screw-type cam chain tensioner adjuster with pressure spring functions automatically
Low-friction coating on piston skirt
Bottom End
Crankshaft, rotor mass centralization, oil circulation, and ignition timing have been carefully examined to help ensure ideal engine braking characteristics
Crankshaft and connecting rod are sintered for additional rigidity
Starting
Features highly reliable auto-decompression system; the dual-weight centrifugal decompression system fitted to the exhaust cam eases starting, and its simple construction helps to ensure reliability
Hot start system gives quick starts when the engine is hot, and the hot start lever is unitized with the clutch lever
The plunger actuating the hot starter has a U-packing seal to prevent water from getting into the carburetion system
Exhaust
Tapered all-titanium exhaust pipe expands in diameter from 38 to 41mm, contributing to both low- and high-rpm performance
Titanium exhaust pipe heat shield
Silencer uses new, long-fiber packing
Cooling
Newly designed, high-capacity Denso radiators deliver superior cooling efficiency
Slim new radiators feature more tightly packed cores and a new fin design for enhanced heat dispersion
Shifting
Four-speed transmission features new shift drum cam to minimize shift lever play
Frame
All-aluminum perimeter frame is composite structure comprising forged, extruded and cast components
The slim profile of the KX450F frame, two-piece radiator shrouds that leave the upper frame spars exposed, and careful design of the remaining bodywork make the KX450F feel light and narrow beneath the rider
Titanium footpegs and footpeg brackets
Aluminum skid plate
Front Suspension
Kayaba AOS (Air-Oil-Separate) fork keeps oil and air in separate chambers for stable damping performance during long motos
Low-friction fork seals contribute to smooth action
Plastic liners inside the fork sliders allow secondary tuning
Rear Suspension
Rear suspension system features linkage ratios to suit the new frame and swingarm
Alloy swingarm uses cast front section, tapered hydroformed spars and forged chain pullers; the tapered spars are shaped to match the balance of flex and rigidity required of the aluminum frame, and allow additional clearance for the rear brake caliper when the rear suspension is fully compressed
Brakes
Front and rear petal disc brakes help reduce unsprung weight
Petal shapes of the discs help clean the brake pads for more efficient braking performance
Wheels
32-spoke rear wheel for reduced unsprung weight
From the Cockpit
Renthal aluminum handlebars are standard
Lightweight short-length grips feature a special pattern to reduce vibration transmitted from the bars to the rider
Seat uses a slip-resistant top surface for good grip when seated and smooth sides for excellent rider mobility
Weight Savings
Aluminum parts used instead of steel, including clutch cable elbow, clutch cable fitting nuts, fuel tank fitting nuts, seat mounting brackets, front brake hose clamp and igniter stay bracket
Options
Optional cable set-up allows manual operation of the decompressor via a lever on the right handle grip
Top mounting clamp for an oversized handlebar
Aluminum and steel rear sprockets with optional tooth sizes
Solid petal brake rotors for wet racing conditions
Optional springs for the front fork and rear shock
20-inch front wheel
SPECIFICATIONS
Engine: Liquid-cooled, four-stroke single with DOHC and four valves
Displacement: 449cc
Bore x stroke: 96.0 x 62.1mm
Compression ratio: 12.0:1
Carburetion: Keihin FCR40
Ignition: Digital AC-CDI
Starting: Kick
Transmission: Four-speed with manual multi-disc wet clutch
Final drive: Chain
Frame: Aluminum perimeter
Rake / trail: 27 degrees / 4.6 in.
Front suspension / wheel travel: 48mm inverted AOS-type telescopic fork with 22-way compression damping and 20-way rebound damping / 12.4 in.
Rear suspension / wheel travel: UNI-TRAK® linkage system with 22-way compression and rebound damping, and fully adjustable spring preload / 12.4 in.
Front tire: 80/100-21 51M
Rear tire: 100/90-19 57M
Front brake: Single semi-floating 250mm petal disc with dual-piston caliper
Rear brake: Single 240mm petal disc with single-piston caliper
Overall length: 86.0 ins.
Overall width: 32.3 ins.
Overall height: 50.4 ins.
Wheelbase: 58.5 ins.
Ground clearance: 13.6 ins.
Seat height: 38.0 ins.
Dry weight: 220.1 lbs.
Fuel capacity: 1.9 gal.
Color: Kawasaki Lime Green / Black
MSRP (USA): $6,799
2006 Kawasaki KX250F
A dramatic makeover for 2006 - more power and a new aluminum frame!
Just two short years after it was introduced to American motocross racers, the championship-winning KX™250F motorcycle has been revamped – even though it already has five titles under its proverbial belt. Numerous changes have been made to the potent KX250F. It produces significantly more power than the 2005 model it replaces, and like the new flagship KX450F, the KX250F sports an all-aluminum perimeter frame. The 249cc, liquid-cooled, four-stroke engine now gives the KX250F a harder-hitting powerband, especially from mid- to high-rpm, and it extends that smooth, traction-grabbing power into the over-rev range. Additional enhancements include revised intake and exhaust ports, and a revised combustion chamber for stronger low- to mid-rpm performance, while new cam profiles and a higher 13.5:1 compression ratio improve high-rpm performance.To compensate for the increased output, the piston now has a thicker crown. Other engine modifications include stiffer valve springs to help ensure reliable valve control at high rpm; a surface-hardened crankshaft for additional rigidity; more efficient oil pumps that increase oil flow by nearly 20 percent; a new stick ignition coil that reduces overall weight; and newly designed, high-capacity Denso radiators
that deliver superior cooling performance due to their more tightly packed cores and new fin design. Kawasaki also revised the timing and lift of the decompression system, so starting the KX250F is said to be easier. The clutch and five-speed transmission have also been modified to include new friction plate material and stiffer clutch springs for improved clutch feel, and the gears have beefier dogs to match the more-powerful engine. Kawasaki engineers have also given the KX250F shift drum a new cam to improve shifting feel. The most visible change to the KX250F is the aluminum perimeter frame. As with the KX450F, Kawasaki engineers combined their experience designing steel perimeter KX frames and techniques used to construct the Ninja® ™ ZX -10R sport bike chassis to create an all-new aluminum perimeter frame. Comprised of forged, extruded and cast aluminum parts, the strong but light design gives the KX250F the best possible balance of torsional and longitudinal rigidity necessary for superior handling characteristics. The frame was designed so that the center of gravity and key chassis dimensions would work together to enhance the rear tire’s ability to drive the KX250F forward instead of squatting under acceleration. Additionally, the four-stroke engine sits in an upright position within the new frame to further aid overall traction. The slim profile of the KX250F frame, two-piece radiator shrouds that leave the upper frame spars exposed, and careful design of the remaining bodywork make the KX250F feel light and narrow beneath the rider.
The KX250F’s high-performance suspension has been designed to complement the new frame. Up front, a Showa twin-chamber fork keeps the oil and air in separate chambers
for consistent damping performance during long motos. On the rear, a new UNI-TRAK® rear suspension system, featuring an alloy swingarm with tapered spars and revised linkage ratios maximizes traction under acceleration. Front and rear petal disc brakes provide stopping power for the KX250F. This design not only helps to reduce unsprung weight, but the petal shape of the discs helps to clean the brake pads for more efficient braking performance. In addition to aggressive new bodywork and a new seat, the KX250F comes with a Renthal aluminum handlebar and an aluminum skid plate as standard. To minimize overall weight, the KX250F utilizes aluminum instead of steel for several components, including the clutch cable elbow, clutch cable fitting nuts, fuel tank fitting nuts, seat mounting brackets, front brake hose clamp and igniter stay bracket. Kawasaki engineers also eliminated the upper mounting brackets of previous designs for the plastic fork protectors.
Optional parts for the KX250F include magneto rotors with different inertias, a 12-tooth countershaft sprocket, top mounting clamp for an oversized handlebar, aluminum and steel rear sprockets, solid petal brake rotors for wet races, different springs for the front fork and rear shock, manual decompression lever and cable, and a 20-inch front wheel.
FEATURES
Engine
249cc, liquid-cooled, four-stroke engine delivers hard-hitting power from mid- to high-rpm
Wide powerband extends smoothly into the over-rev
Top End
Revised intake and exhaust ports, and revised combustion chamber improve low- to mid-range performance
Rev-limiter settings and ignition timing have been revised to extend the engine’s over-rev capability
New cam profiles help increase high-rpm performance without sacrificing low-end performance
Piston features a thicker crown to compensate for increased power and higher compression ratio
Once-piece magneto rotor offers improved reliability
New stick ignition coil saves weight and offers improved performance
Bottom End
Crankshaft is surface-hardened for additional rigidity
Countershaft sprocket has more – and smaller – splines to increase reliability
More efficient oil pumps increase oil flow by nearly 20 percent
Cooling
Newly designed, high-capacity Denso radiators are slimmer
Radiator features more tightly packed cores and a new fin design to deliver superior cooling efficiency
Shifting
New friction plate material and stiffer clutch springs improve clutch feel
New clutch lever design compensates for higher spring rate
Five-speed transmission dogs are beefier to match the engine’s increased power
Shift drum features new cam for improved shifting feel
Frame
All-aluminum perimeter frame features composite structure, utilizing forged, extruded and cast components
The slim profile of the frame, two-piece radiator shrouds that leave the upper frame spars exposed, and careful design of the remaining bodywork make the KX™250F feel light and narrow beneath the rider
Front Suspension
Showa twin-chamber fork keeps oil and air in separate chambers for stable damping performance during long motos
Rear Suspension
New UNI-TRAK rear suspension system features revised linkage ratios to suit the new fame and swingarm
Alloy swingarm uses cast front section, tapered hydroformed spars and forged chain pullers; the tapered spars are shaped to match the balance of flex and rigidity required of the aluminum frame, and allow additional clearance for the rear brake caliper when the rear suspension is fully compressed
Smaller rear chain guide reduces overall weight
Brakes
Front and rear brakes utilize new petal discs, helping to reduce overall weight
Petal discs help to clean the brake pads for more efficient braking performance
Wheels
New rear wheel helps to reduce unsprung weight
From the Cockpit
Renthal aluminum handlebar is strong and reduces overall weight
Short-length grips feature a special pattern to reduce vibration transmitted from the bars to the rider
New Styling
New bodywork and new seat have aggressive style
Options
Different inertia magneto rotors
12-tooth countershaft sprocket
Top handlebar clamp for an oversized bar
Aluminum and steel rear sprockets with optional tooth sizes
Solid petal brake rotors for wet racing conditions
Optional springs for the front fork and rear shock
Manual decompression lever and cable
20-inch front wheel
SPECIFICATIONS
Engine: Four-stroke single with DOHC and four valves
Displacement: 249cc
Bore x stroke: 77.0 x 53.6mm
Cooling: Liquid
Carburetion: Keihin FCR37 and hot start circuit
Compression ratio: 13.5:1
Ignition: Digital AC-CDI
Transmission: Five-speed with wet multi-disc manual clutch
Final drive: Chain
Frame: Aluminum perimeter
Rake / trail: 27.5 degrees / 4.7 in.
Front suspension / wheel travel: 47mm inverted twin-chamber telescopic fork with 16-way compression and rebound damping / 12.4 in.
Rear suspension / wheel travel: UNI-TRAK® linkage system with 13-way low-speed and 2-turn highspeed compression damping, 17-way rebound damping and fully adjustable spring preload / 12.2 in.
Front tire: 80/100-21 51M
Rear tire: 100/90-19 57M
Front brake: Single semi-floating 250mm disc with dual piston caliper
Rear brake: Single 240mm disc with single-piston caliper
Overall length: 85.0 ins.
Overall width: 32.3 ins.
Overall height: 50.0 ins.
Ground clearance: 14.6 ins.
Seat height: 37.8 ins.
Dry weight: 204 lbs.
Wheelbase: 57.8 ins.
Fuel capacity: 1.9 gal.
Color: Kawasaki Lime Green / Black
MSRP (USA): $5,899
2006 KAWASAKI KX250
The Two-Stroke returns!
The KX250 should be even better for 2006 as Kawasaki has fine tuned the engine, suspension and brakes. To make this 250 Supercross race winner quieter, the 249cc, liquid-cooled, two stroke engine features a new piston profile, while a longer, wider silencer ensures the KX250 meets modern noise emission standards. Plus, the silencer’s all-new, long-fiber packing is more durable and requires less maintenance. And to keep the KX250 at the best-possible temperature, a new water pump impeller increases coolant circulation.Changes to the KX250’s chassis include a strong, lightweight Renthal aluminum handlebar, and the rear shock now features dual compression adjustability so riders have more tuning options for both low-speed and high-speed compression damping. Up front, the Kayaba AOS fork has a new, one-piece sleeve to improve suspension action at full compression. For 2006, the KX250 has even stronger stopping power. The new petal-style disc brakes are not only lighter, but their shape helps to clean the brake pads for more efficient braking performance.
The KX250 also features a new look for 2006, with aggressive new graphics and a new, two-tone seat.
FEATURES
Engine
New piston profile helps to reduce mechanical noise
Copper-plated steel washer improves cylinder head’s sealing performance
KIPS® power valve O-ring offers improved sealing performance
New reed valve stopper features new shape to improve low-rpm response – revised shape improves scavenging efficiency by facilitating airflow through the third scavenging port
New water-pump impeller increases coolant circulation for improved high-rpm and over-rev performance
Primary gear is now secured using a key and lock-nut to help reduce mechanical noise
New kickstart lever has revised shape and mounting angle for improved durability
New silencer is slightly wider and nearly two inches longer to ensure the KX™250 meets stricter noise emission standards
New long-fiber silencer packing is more durable and requires less maintenance
Chassis
Renthal aluminum handlebar is strong and lightweight
Front and rear petal disc brakes help to reduce unsprung weight
Petal-shaped discs help to clean the brake pads for more efficient braking performance
Rear shock now features dual compression adjustability so riders have more tuning options for both lowspeed and high-speed compression damping
Fine-tuning to the Kayaba AOS (Air-Oil-Separate) fork via a new one-piece plastic sleeve inside the fork inner tubes improves suspension action at full compression
New Styling
Aggressive Kawasaki Lime Green and black graphics are matched by a two-tone seat
Options
Carburetor tuning parts
Different inertia magneto rotors
Larger countershaft sprocket
20-inch front wheel
Solid brake discs for wet racing conditions
Aluminum and steel rear sprockets
Optional fork and shock springs
Steel spoke nipples
Front and rear wheel assemblies
SPECIFICATIONS
Engine: Two-stroke single with KIPS®
Displacement: 249cc
Bore x stroke: 66.4 x 72.0mm
Cooling: Liquid
Carburetion: Keihin PWK38S with Power Jet
Induction: Piston reed valve
Compression ratio: 10.5 (low speed) – 9.1 (high speed):1
Ignition: Digital CDI
Transmission: Five-speed
Final drive: Chain
Frame: Perimeter style, high-tensile steel with aluminum subframe
Rake / trail: 26 degrees / 4.1 in.
Front suspension / wheel travel: 48mm inverted cartridge-type telescopic fork with 16-way compression and rebound damping / 11.8 in.
Rear suspension / wheel travel: UNI-TRAK® linkage system with 18-way low-speed compression and 2-turn high-speed compression damping, plus 16-way rebound damping and fully adjustable spring preload / 12.2 in.
Front tire: 80/100-21 51M
Rear tire: 110/90-19 62M
Front brake: Single semi-floating 250mm petal disc with dual-piston caliper
Rear brake: Single 240mm petal disc with single-piston caliper
Overall length: 86.0 in.
Overall width: 32.1 in.
Overall height: 49.8 in.
Ground clearance: 13.4 in.
Seat height: 38.0 in.
Dry weight: 213.9 lbs.
Wheel base: 58.3 in.
Fuel capacity: 2.2 gal.
Color: Kawasaki Lime Green / Black
MSRP (USA): $5,999
2005 KX250F Test | 2005 KX250 Quick Ride
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