KX250 (MY21) – Kawasaki

The KX design philosophy – Put mid-level to expert riders on the top step of the podium. Designed to continue the KX250 history of winning – in the extremely competitive 4-stroke 250cc class Kawasaki race machines have the most AMA Supercross and Motocross titles – the 2021 model KX250 builds on the engine changes from the previous year to deliver even greater power and an even higher rev limit, plus electric start and a hydraulic clutch.

ENGINE

Despite the 2020 KX250 already benefitting from a significant power increase thanks to its adoption of finger-follower valve actuation like the KX450, additional changes for 2021 raise peak power even further and enable an even higher rev limit, while significantly increasing low-mid rpm performance. As before, dual injectors, downdraft-style intake, and race inspired tuning and parts add to performance.

The new engine boasts an increase in peak power of approximately 1.0 kW (1.4 PS), and the rev limit increases a further 350 min-1 to 14,500 min-1. A significantly more robust low-mid range is complemented by strong high-rpm performance that gives riders an advantage on the straights, and, when combined with a higher rev limit, makes it easier to tie corners together for quicker lap times.

Like the KX450, the KX250 features a valve train designed by Kawasaki’s World Superbike engineers. Finger-follower valve actuation enables a higher rev limit and more aggressive cam profiles – both contributing to high-rpm performance.

Like the KX450, a hydraulic clutch offers direct feel and light lever action. Less play as the clutch heats up during heavy use results in more consistent feeling. The use of coned-disc springs contributes to lighter clutch actuation when the lever has been pulled in, and a wider clutch engagement range, which facilitates control (especially when half-clutching).

SUSPENSION AND BRAKES

Steering head area with optimised rigidity, main frame rails with revised cross-sections, and a revised line for the swingarm brackets contribute to the overall rigidity balance. Wider lower frame rails also contribute to overall rigidity balance. KX450 swingarm delivers the rigidity to match the frame, and contributes to increased rear traction. Chassis balance and settings were all set to suit race-experienced riders.

High-performance KYB ø48 mm inverted coil-spring fork handles suspension duties up front. Its large-diameter inner tubes enable the use of large ø25 mm damping pistons, delivering smooth action and firm damping. Lower triple-clamp with revised rigidity and revised linkage ratios contribute to increased absorption and damping performance.

New KX450 front master cylinder adds to the high level of control and feedback from the front brake. A smaller-diameter rear disc ø240 mm offers performance optimised for the KX250. The stylish discs contribute to both sporty looks and a high-quality appearance.

FRAME

An evolution of the current design, the new frame offers a better overall rigidity balance. While many parts are common with the KX450’s frame, the cast parts (like the shock tower mount and engine hangers) were designed specifically for the needs of the KX250.

Complementing the KX250’s sleek new bodywork, factory-style graphics ensure it is the sharpest looking bike in the paddock and further reflect its highly-tuned performance. Coloured highlights on the suspension adjusters and engine oil cap and generator cover plugs contribute to a distinctive Kawasaki look.

The narrow frame and minimalistic bodywork offer a slim riding position that facilitates control. A low, flat tank/seat design makes it easier to sit farther forward, and long, smooth surfaces make it easy to slide back and forth.