KX250F
Kawasaki focused on further improving performance in the high-rpm and over-run ranges of the KX250F. How? By adding a new cylinder head with titanium valves, larger and smoother intake ports as well as a tapered titanium exhaust pipe that's 10-mm longer -- again to increase performance at high rpm.

Mechanical losses have been carefully dealt with by engineers to ensure that maximum power is transferred to the ground. Enhancements include:

· Lowering the amount of engine oil (1.0L instead of 1.5L) contributes to overall weight reduction;

· Changing the cam chain tensioner spring to one with a lower load reduces mechanical loss by approximately 30%;

· Revising ignition timing improves feeling at low-mid rpm.
The transmission of the new KX250F is also improved thanks to a new ratchet drive system (like that on the KX450F) in place of the gear-driven system of the previous model. The result is improved shift feeling. The clutch has not been overlooked either: lever ratios, spring rates and shaft locations were all reevaluated to deliver quicker, sharper gear shifts.

2009 Kawasaki KX 250 F

Common improvements and innovations
Both the Kawasaki KX450F and KX250F are built on the same new aluminum frame. Lighter yet more rigid than the old KX frame, it incorporates several key upgrades, such as:

· A 400-gram lighter swingarm;

· A finer, oval-shaped down tube allowing superior rigidity balance while reducing weight by 800 grams;

· Slimmer radiators for increased efficiency;

· Engine side covers made from synthetic materials;

· A narrower drive chain guide for a 100-gram weight reduction;

· A higher swingarm pivot for improved rear-wheel traction;

· New, wider footpegs offering increased grip and feel to the rider;

· And a larger synthetic skid plate for the engine, offering greater protection without increasing weight.

With such notable improvements to the chassis and a sizeable power increase, the 2009 Kawasaki KX450F and KX250F have all the ingredients to dominate their respective classes.


Photo Credit : Kawasaki