Kawasaki KX250F Factory Tuning And Fuel Injection to keep expert riders at the front of the pack


Filed Under (Kawasaki) by admin on 08-02-2011

Battery-less fuel injection system Designed specifically for motocrossers, the fuel injection system incorporates a small lightweight ECU and operates without a battery to further eliminate unnecessary weight. And of course, fuel injection eliminates the need to adjust engine settings to suit track and climate conditions. Ensuring quick starting without a battery was a prime directive when developing this fuel injection system. Using only electricity generated by the kick starter, the engine can be started with only three rotations of the crankshaft. The system delivers electricity in the following order:1) ECU, 2) fuel pump, 3) injector. With a warm engine, starting can be accomplished in a single kick. The compact, lightweight ECU, located just in front of the steering head (behind the number plate), was designed specifically for motocross use. To help cope with the shocks and vibrations of motocross riding, the fuel pump relay is built into the ECU. A 43 mm throttle body makes use of a progressive throttle link to deliver airflow in much the same way as would a FCR carburettor. Using two linked shafts, the throttle body opens more quickly after the 3/8 open position, delivering sharp response and excellent power. Lightweight throttle body is approximately half the weight of a FCR carburettor – a weight savings of about 600 g. To ensure the high-rpm engine’s demand for a high flow of fuel in a short period is met, the KX250F’s injector features larger holes than that used on the KX450F. A fine atomising injector with 4 holes disperses spray particles with a droplet size of 120 ┬Ám. Fuel flow is about 20% greater than on the KX450F. The newly designed fuel pump, located in the fuel tank, is a lightweight aluminium construction. (Fuel tank capacity is now 7.2 litres.)