Continuing the theme of Supercross and motocross success, the new model year KX250 will reward the commitment shown by both professional and eager amateur riders taking the Kawasaki quarter litre capacity MX concept to the next level.
Leading the new thinking – and as the result of Kawasaki official team feedback during the current season – the front fork (along with key engine and other chassis modifications) illustrates well how seriously the Akashi factory takes off-road sport.
Chief among the front fork changes is the adoption of a Kayaba assembly incorporating
a new high-performance ø48 mm inverted coil-spring fork. The large-diameter inner tubes enable the use of large damping pistons, delivering smooth action and firm damping. Stiffer spring rates front and rear match the KX250’s increased power. The fork’s improved ability soak up bumps at the initial part of the stroke is complemented by increased firmness for handling large impacts and matched to the rear shock which features dual compression adjustability, allowing high-speed and low speed damping to be tuned separately.
Speaking of power, the headlines are dominated by changes to the cylinder head group and induction modifications. Featuring finger follower valve actuation most recently adopted by the Superbike world championship wining Ninja ZX-10RR, this new direction facilitates a higher rev celling and more aggressive camshaft timing whilst reducing overall valve train weight. Boasting an increase in peak power of approximately 2.4 kW (3.3 PS), and performance focused on the high-rpm range, the stronger high-rpm performance is easily noticeable from 10,000 min and gives riders a special advantage on the straights. Combined with a higher rev limit, it’s now easier to tie corners together for quicker lap times.
Additionally, a revised airbox construction features a shorter (120 mm > 70 mm) tapered intake funnel, which contributes to increased high-rpm performance. Another KX250 innovative feature is the dual injectors - a feature since 2012 - utilising an injector downstream of the throttle valve (where injectors are located on standard FI systems). With that in mind, the larger diameter (ø43 mm >> ø44 mm) throttle body flows a greater volume of air, contributing to increased high-rpm performance, while repositioning the intake duct allows an even straighter approach for intake air. Finally, downdraft-style intake routing increases the intake air’s approach angle into the cylinder from 29.5º to 32.5º, improving cylinder-filling efficiency and contributing to increased engine power.
These stand-out features – along with a long list of clever additional updates - combine to create the most powerful production KX250 four-stroke yet and a prime candidate for podium topping rides.
Within an environment where not simply winning on track is of prime importance but also meeting and exceeding the efforts of rival manufacturer’s, Kawasaki has once more taken the highly successful KX250 concept to an even higher level.
As machines soon become available in European dealers, committed and motivated Team Green enthusiasts, plus the huge number of Kawasaki focused off-road teams, will be able to experience first-hand the “most powerful yet” KX250.