With more Supercross and Motocross championships than any other manufacturer, the KX name is synonymous with winning. The KX450 motorcycle represents the flagship of the KX lineup, built with the sole purpose of dominating the track. Over the past four decades, we’ve learned what it takes to win and stay on top. Our dedication to building the ultimate machine is undeniable, and the KX450 represents this to the fullest.
Recognized as the most powerful motocrosser in the paddock, the KX450 boasts innovative engine technology inspired by Kawasaki’s race machines. Features like finger-follower valve actuation and a bridged-box bottom piston that contribute to its lofty performance are backed by electric start and a hydraulic clutch, further elevating its race-winning potential.
The high-acclaimed KX450 engine delivers hard-hitting power, while its flat torque curve makes it easy to get on the gas. Finger-follower valve actuation (a valve train designed by Kawasaki’s World Superbike engineers) enables large-diameter valves and aggressive cams. Downdraft-style intake and friction-reduction efforts (like a dry film lubricant on the piston skirt) further contribute to the high performance.
Being able to restart an engine quickly during a race can mean the difference between keeping your lead, or having to fight your way back through the pack. Electric start makes restarting the engine as easy as pushing a button.
The hydraulic clutch offers direct feel and light lever action. Revised construction using coned-disc springs results in lighter clutch actuation when the lever has been pulled in, and a wider clutch engagement range, which facilitates control (especially when half-clutching).
Lightweight and designed for the rigours of off-road riding, the ECU contains multiple programmable engine maps to offer riders an advantage on the race course. Using the provided DFI couplers, riders are able to easily switch from one to another of the three engine maps to suit riding conditions. The plug-and-play style system is quick, easy and stress-free. Each of the three maps can be reprogrammed using the optional KX FI Calibration Kit.Non-current colour shown
Factory-style launch control system increases the chance of getting a good start by helping riders maximise grip when starting on a low-traction surface.
Trimmed of all unnecessary material, this is the leanest KX450 chassis to date. Frame, suspension, brakes and ergonomics have all been optimized to make the KX450 even better equipped to turn quick lap times.
Complementing the powerful engine, light, nimble handling contributes to the KX450’s quick lap times. Thanks to extensive weight-reduction efforts, the lightweight aluminium perimeter frame contributes to a highly-competitive, low overall weight of only 110.2 kg.
Handling suspension duties up front is a high-performance o49 mm inverted coil-spring fork. The large-diameter inner tubes (the same size as on our factory racers) enable the use of large damping pistons, delivering smooth action and firm damping. At the rear, New Uni Trak rear suspension contributes to superb rear-wheel traction.
The oversized o270 mm semi-floating front disc complemented by a o250 mm disc at the rear deliver strong stopping power and a high level of control.
The narrow frame and minimalistic bodywork offer a slim riding position that facilitates control.
A choice of four handlebar positions and two footpeg positions allows riders to tailor their riding position to suit body size and preference. Factory-style o28.6 mm (1-1/8”) Renthal aluminium Fatbar helps reduce vibration and shocks transmitted to the rider, while a lower, closer grip position helps put the rider in a position that makes it easier to weight the front wheel.
4-stroke Single
449 cc
96.0 × 62.1 mm
12.5:1
DOHC, 4 valves
Fuel injection: o44 mm x 1
Digital DC-CDI
Electric
Liquid-cooled
Forced lubrication, semi-dry sump
5-speed, return
2.727 (60/22)
1.750 (28/16)
1.412 (24/17)
1.188 (19/16)
1.000 (19/19)
0.875 (21/24)
3.846 (50/13)
Wet multi-disc, manual
Chain
Perimeter, aluminum
o49 mm inverted fork with adjustable compression and rebound damping
New Uni Trak with adjustable dual-range (high/low-speed) compression damping, adjustable rebound damping and adjustable spring preload
305 mm
307 mm
27.6?
122 mm
42? / 42?
80/100-21 51M
120/80-19 63M
Semi-floating o270 mm petal disc
Dual-piston
o250 mm petal disc
Single-piston
2,185 × 820 × 1,265 mm
1,485 mm
340 mm
955 mm
110.4 kg
105.8 kg
6.2 litres
KX450JPFNN