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Sep 21, 2023

2023 Kawasaki KX450SR Guide • Total Motorcycle

Introducing the 2023 Kawasaki KX450SR… Featuring special tuning and

Introducing the 2023 Kawasaki KX450SR…

Featuring special tuning and elite-level racing components, the limited-edition KX450SR motorcycle is built to win right out of the box. This bike is designed to further elevate the performance, durability, and styling of the already championship-proven KX450 platform by partnering up with the most respected names in the sport. With only limited quantities available, now is your chance to cross the finish line first with this one-of-a-kind race machine.

After finding abundant success in its debut in 2022, the new KX450SR makes its highly anticipated return for 2023. Previously only reserved for early Kawasaki factory racing machines, the "SR" or Special Racer naming convention represents the pinnacle of Kawasaki race bikes. The KX450SR is purpose built leveraging significant high value parts that have been proven by the Monster Energy Kawasaki race team competing in Monster Energy Supercross and AMA Pro Motocross Championships.

Starting with the KX450 concept, the new KX450SR model has been designed to suit riders seeking race wins and features elite-level racing components, special tuning and design elements inspired by the Monster Energy Kawasaki race team to further elevate its performance and factory racer looks.

For 2023, this high-performance, limited edition Special Racer is now equipped with SHOWA front and rear suspension components.

ENGINE

The 449cc lightweight engine package utilizes input derived directly from the Monster Energy Kawasaki race team. Just like the KX450, the KX450SR engine features an electric start activated by the push of a button and powered by a compact Lithium-ion battery. A lightweight finger-follower valve actuation design comes by way of Kawasaki's top-level road racing technology and World Superbike engineers, enabling larger-diameter valves and more aggressive cam profiles. The KX450SR features polished intake ports that provide smoother airflow, contributing to increased engine performance. A close-ratio five-speed transmission is paired with a high-capacity coned disc-spring hydraulic clutch that helps facilitate control and provide a consistent feeling even under heavy use.

Just like the Monser Energy Kawasaki factory race team, a lightweight Pro Circuit Ti-6 Pro titanium race exhaust has been fitted and contributes to increased engine performance. Engine ECU fuel injection settings are exclusive to the KX450SR and match the more powerful engine characteristics, providing controllability and factory-spec high-performance riding for a wide-range of motocross riders.

CHASSIS

A slim aluminum perimeter frame provides precise cornering through excellent front-end feel and agility when riding at high speeds. The frame's lightweight construction is composed of forged, extruded, and cast parts, while the engine is used as a stressed member and adds to the frame's rigidity balance. Engineers carefully selected the dimension of the swingarm pivot, output sprocket and rear axle locations to focus on the center of gravity and balanced handling.

SUSPENSION

NEW SHOWA front and rear suspension componentsThe KX450SR receives new SHOWA front and rear suspension components with a TiO (titanium oxide) on the inner fork tubes that improves wear resistance and reduces friction. Large-diameter inner fork tubes are the same size found on Kawasaki's factory racing team and allow for the use of large 39mm compression damping pistons and a 25mm cartridge cylinder, providing smooth action and firm damping. The inner surface of the outer fork tubes feature SHOWA's Dimplush texture, which has a wave-like finish to help retain an oil film for smoother action. The Dimplush texture also has a Kashima coating to create a low-friction surface that helps prevent wear so the sliding surfaces remain smooth for a long time. Suspension settings have been optimized on the KX450SR in order to achieve higher performance, smoother suspension action, and provide a plush feeling. The SHOWA rear shock offers dual compression adjustability so that high speed and low speed damping can be tuned separately. Utilizing feedbck from Kawasaki's factory race teams, the 22mm front axle enhances front end traction. The New Uni-Trak rear suspension linkage ratios have been selected to suit the chassis.

Holding up the SHOWA front forks is a set of XTrig ROCS (revolutionary opposing clamp system) tech triple clamps that help to improve fork flex action for more optimal fork function. The upper triple clamp is outfitted with XTrig's PHDS (progressive handlebar dampening system) handlebar mounts that are lightweight and improve responsiveness of the fork, and is supported by elastomers which are designed to absorb vibration from the engine and chassis. This system also helps to dampen the forces acting on the handlebars in both horizontal and vertical directions, translating into increased steering precision for the rider. With this system, the handlebar can be adjusted in 12 different positions for total rider customization.

BRAKES & WHEELS

Adorning the KX450SR is a pair of D.I.D. DirtStar wheels, improving the strength and durability under the most challenging conditions on the racetrack. The black coating on the rims emulates the looks of a factory race machine. Further adding to the attention grabbing appearance on the KX450SR is the championship proven combination of a D.I.D. 520ERT3 gold chain fitted to a black Renthal Ultralight aluminum rear sprocket.

Handling the stopping duties is an oversized 270 mm, petal-shaped front brake rotor from the renowned manufacturer, Braking. The rear is equipped with a 250 mm petal-shaped Braking rotor coinciding with the large front disc.

ERGONOMICS

Kawasaki continues its unmatched commitment towards providing riders with class-leading ERGO-FIT adjustable componentsto fit a variety of riders and riding styles. The footpegs feature dual-position mounting points, with a lower position that reduces the standard setting by an additional 5 mm, reducing the knee angle when taller riders are seated.

STYLING

In addition to the already sharp, aggressive styling found on the KX450, the KX450SR showcases special colors & graphics that resemble those found on the Monster Energy Kawasaki race team. Also adding to its true race machine looks is a Hinson Billetproof clutch cover featuring the Kawasaki Racing Team logo that improves heat dissapation as well as a Pro Circuit Ti-6 Pro titanium exhaust that features a special green decal.

Factory-style Details• Polished intake ports help smooth airflow to the combustion chamber for more efficient cylinder filling and increased performance.• Pro Circuit Ti-6 Pro titanium race exhaust system is lightweight and helps improve power.• Special FI mapping provides powerful yet controllable engine characteristics for high-performance riding for a wide range of riders.• Exclusive KX450SR suspension settings for increased suspension performance and closer resemblance to the Monster Energy Kawasaki factory racer.• XTRIG ROCS-TECH triple clamps, used by the Monster Energy Kawasaki factory team, have opposing split clamp areas that help improve fork flex action for more optimal fork function.• Upper triple clamp fitted with XTRIG's Progressive Handlebar Dampening System (PHDS) so that the handlebar is supported by elastomers designed to absorb engine and chassis vibrations. The system also dampens the forces acting on the handlebar in a horizontal and vertical direction for increased steering precision. The handlebar can be adjusted in 12 different positions to suit various rider sizes and preferences.• DID Dirt Star ST-X aluminum alloy rims, used by the Monster Energy Kawasaki factory team, are strong, lightweight and add a factory touch.• DID gold chain with Renthal rear sprocket as well as Hinson clutch cover add to the factory appearance.• Special graphics complete the factory look.

The engine has potent peak power while a flat torque curve makes it easy to accelerate and find traction. Kawasaki's multi-time World Superbike Championship-winning engineers designed the finger-follower valve train that, combined with minimal friction loss and steep downdraft style intake tract, contributes to the power.

4-Stroke Engine• Light piston helps minimize reciprocating weight and contribute to engine performance. The piston features a similar bridged-box bottom design featuring fully flush internal bracing as those used on the factory racers, with a short skirt and reinforced external ribs resulting in a lighter, stronger piston.• The piston skirt is coated with a dry film lubricant to reduce friction between the piston and cylinder for increased performance.• Plain bearings at the connecting rod big end reduce mechanical loss and help boost power.• Cylinder offset is 8.5mm forward to reduce friction and enable more efficient power generation.• Wedge-shaped crank web increases offsetting moment for a balance factor close to 60 percent, which is close to the factory bike. The high balance factor contributes to reduced engine vibration, smoother power delivery and increased performance, especially at low rpm where response is noticeably snappier.• Aluminum cylinder with chrome composite plating(KP) provides rapid heat transfer, superb wear resistance and optimum lubrication retention for increased performance and durability.• Semi-dry sump(KP) lubrication system for quicker engine response. The majority of oil is stored in the transmission to keep excess oil away from the crankshaft and prevent power-robbing stirring loss. A shallow chamber collects oil at the bottom of the crankcase, where a scavenge pump moves it to the transmission. This allows the crank to be located as low as possible to help lower the center of gravity.

Race-tuned 4-Valve Cylinder Head(KP)• Finger-follower valve train designed by Kawasaki's multi-time World Superbike Championship winning engineers allows large diameter valves, aggressive cam profiles and high rev limit for high-rpm performance.• Finger-follower valve actuation reduces valve train mass by approximately 6.5 percent compared to tappet-style actuation, as well as reducing friction at the cam lobe. DLC (Diamond-Like Carbon) coating on the followers help prevent wear.• Aggressive camshaft lobes have a chromium nitride coating for durability.• 40mm intake and 33mm exhaust valves are titanium to help reduce weight.• Chromium steel valve spring retainers are also light and provide reliable valve control at high rpm.• When the cylinder head is cast the intake port cores are coated so that they have extremely smooth surfaces for increased intake efficiency.

ENGINE

Downdraft Intake• Downdraft-style intake routing has a 20˚ approach angle for a straight approach for intake air that enhances cylinder filling efficiency and contributes to power.• 44mm throttle flows abundant air for maximum performance, especially at high rpm and overrun. A reversed orientation tilts the butterfly valve open from the top for optimum fuel atomization from the top-mounted injector.• Fine atomizing, 12-hole injector sprays 75 micron droplets and contributes to smooth power delivery and superb engine response at partial throttle.

Pro Circuit Ti-6 Pro Exhaust• Long header pipe contributes to robust low-end power.• Exhaust system features a resonator chamber to effectively increase exhaust pipe length and reduce exhaust noise.

Coned Disc-spring Hydraulic Clutch [8]• The clutch uses a single coned disc spring instead of five coiled springs for light clutch actuation when the lever is pulled and a wide clutch engagement range that helps the rider control the clutch.• Large diameter clutch plates and special friction plate material help to resist clutch fade. The friction plates also have offset segments to promote clean separation of the discs to help reduce drag when the clutch is disengaged.• Kawasaki's hydraulic clutch offers direct feel and light lever action. Less play as the clutch heats up during heavy use results in a more consistent feel.

Electric Start• Provides the convenience of quick and easy pushbutton engine starting.• Powered by a lightweight, compact lithium-ion battery that helps keep weight gain to a minimum.• Automatic centrifugal compression release system on the exhaust cam lifts one exhaust valve to facilitate starting. The system's simple construction is light weight and highly reliable NOTE: Only use Lithium-ion specific battery charger tohelp prevent fatal battery damage.

Easy DFI Tuning• Riders can change DFI settings by simply replacing a coupler located on the right side of the steering stem. Riders can choose between Standard, Hard or Soft terrain settings to suit riding conditions.

Hand Held Easy-to-Use KX FI Calibration Kit (Optional)• Accessory KX FI Calibration Kit features a handheld controller that enables users to adjust engine characteristics trackside simply by plugging the controller into the engine's ECU.• The kit's user interface is easy to understand and easy to use.• Seven different maps come loaded on the controller to adjust the ECU to suit track conditions. Additional maps can be created and stored on the hand held controller, or on a PC with data transfer between the controller and PC performed via SD card.• When connected to the ECU, the controller can be used to display the status of a running engine.• Can be used on all KX models equipped with DFI.

Launch Control Mode• Similar to the system used on the Monster Energy Kawasaki factory racers, allows riders to activate a separate engine map designed to assist them get holeshots by pressing a button.• The Launch Control Mode map retards ignition timing, allowing the tire to gain grip in low traction situations, and allowing riders to focus on their lines.• Even for top-level riders, controlling the massive power of the KX450 off the start requires throttle control and clutch finesse. By slightly reducing this power, Launch Control Mode helps riders maximize traction and increase the chance of getting a good start.• Launch Control Mode has the greatest effect within the first few seconds of releasing the clutch off the start – the most crucial time to get ahead of rivals for better positioning going into the first corner.• Activated when the engine is running by pressing and holding the launch control button, located at the left handlebar, for two seconds or more while in neutral, first or second gear. When activated, the indicator lamp next to the button flashes quickly to let the rider know the system is engaged.• The system automatically disengages when the transmission is shifted into third gear, switching back to the normal engine map.• The Launch Control Mode indicator light also serves as a warning light if the DFI system malfunctions.

Aluminum Perimeter Frame (KP) [10]• The engine is used as a stressed member, contributing to the frame's rigidity balance.• Steering head area with optimised rigidity, main frame rails, and line for the swingarm brackets contribute to the overall rigidity balance. Wide lower frame rails also contribute to overall rigidity balance.• Down tube combines a forged front portion with cast aluminum rear piece which contributes to better front-end feel.• Composed of a combination of forged, extruded and cast parts, the aluminum frame is designed with a balance of torsional and longitudinal rigidity for quick handling.• Design emphasis on providing maximum traction under acceleration. Specific chassis dimensions and design (reinforcing ribs, swingarm pivot, output shaft, linkage mounts and rear axle) placed to prevent chassis squat and improve traction.

FRAME & SUSPENSION

SHOWA 49mm Coil-Spring Fork• With the success that the Monster Energy Kawasaki Racing Team has achieved using SHOWA suspension, the KX450SR is now equipped with SHOWA fork with exclusive SR settings for increased racing performance and to more closely resemble the Monster Energy Kawasaki Racing Team in appearance and performance. Hard titanium oxide (TiO) coating on the outer surface of the inner sliding fork tubes helps prevent wear, scratches and other damage to the tubes while reducing stiction and improving overall fork action.

New Uni-Trak Rear Suspension• KX450SR-specific suspension settings help increase racing performance.• Compact designed rear shock has large diameter compression adjuster that helps prevent oil cavitation under high frequency movement.• New Uni-Trak rear suspension linkage ratios selected to suit the chassis. The linkage mounts underneath the swingarm allowing additional rear suspension travel yet maintaining a low seat height. The additional rear travel offers improved suspension action over a wider range of track conditions.• Dual compression adjustability allows high speed and low-speed damping to be tuned separately.

Big Brakes• 270mm Braking brand petal front brake disc provides superb stopping power.• Front brake master cylinder provides superb initial control while contributing to overall braking performance.• 250mm Braking brand petal rear brake disc for strong stopping power.• Petal disc shape helps remove dirt build up in pads, increasing performance.A smooth, flat rider interface provides easy rider mobility on the bike.

Slim, Adjustable Ergonomics• Renthal 1-1/8 inch aluminum Fatbar handlebar helps reduce vibration and shocks transmitted to the rider. The bend helps to make it easier for the rider to weight the front wheel.• Wide footpegs provide firm footing.• Bodywork is designed to facilitate rider movement with long, smooth surfaces that ease sliding back and forth on the bike.• The top of the fuel tank is designed to provide a flat progression from the seat to the tank, giving riders great freedom of movement and allowing them to sit far forward.• Radiator shrouds are positioned close to the frame so they are slim where the rider's knees make contact, and the single-piece design make them easy to grip with the legs.• The radiators are turned inward 10 degrees, and combined with the narrow frame spars provide a narrow rider interface.

ERGO-FIT Components• Upper triple clamp provides multiple handlebar clamp mounting positions so that the Renthal handlebar can be set in one of 12 positions.• The footpeg brackets can be mounted in two positions, allowing the rider to change footpegs height by 5mm.

POWER

Engine 4-stroke single, DOHC, liquid-cooledDisplacement 449ccBore x Stroke 96.0 x 62.1mmCompression Ratio 12.5:1Fuel System DFI with 44mm Keihin throttle bodyIgnition Digital CDI with 3 Coupler OptionsTransmission 5-speed, return shift, with wet multi-disc manual clutch and hydraulic clutch actuationFinal Drive Chain

PERFORMANCE

Front Tire 80/100-21Rear Tire 120/80-19Front Brakes Single semi-floating 270mm Braking petal disc with dual-piston caliperRear Brakes Single 250mm Braking petal disc with single-piston caliper

DETAILS

Frame Type Aluminum perimeterOverall Width 32.3 inFuel Capacity 1.64 galColor Choices Lime GreenWarranty Not AvailableKawasaki Protection Plus (optional) Not Available

POWEREngine 449cc, liquid-cooled, 4-stroke, DOHC 4-valve singleBore x Stroke 96.0 x 62.1 mmCompression Ratio 12.5:1Fuel System Fuel injection: ø44 mm x 1Ignition Digital DC-CDIStarting ElectricLubrication Forced lubrication, semi-dry sumpTransmission 5-speed, returnClutch Wet multi-disc, manualFinal Drive Chain

PERFORMANCEFrame Perimeter, aluminumFront Suspension / Wheel Travel ø49 mm inverted fork with adjustable compression and rebound damping / 305 mm (12.0 in)Rear Suspension / Wheel Travel New Uni Trak with adjustable dual-range (high/low-speed) compression damping, adjustable rebound damping and adjustable spring preload / 307 mm (12.1 in)Rake / Trail 27.4° / 121 mmSteering Angle (L/R) 42° / 42°Front Tire 80/100-21 51MRear Tire 120/80-19 63MFront Brake Semi-floating ø270 mm petal disc with dual-piston caliperRear Brake ø250 mm petal disc with single-piston caliper

DETAILSDimensions (L x W x H) 2,185 x 820 x 1,265 mm (86.0 x 32.3 x 49.8 in)Wheelbase 1,485 mm (58.5 in)Road Clearance 340 mm (13.4 in)Seat Height 955 mm (37.6 in)Curb Mass** 110.4 kg (243 lb)Mass Without Fuel 105.8 kg (233 lb)Fuel Capacity 6.2 litres

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Manufacturer Specifications and appearance are subject to change without prior notice on Total Motorcycle (TMW).