As for intake, the engine of the YZ250F retains a 5-valve cylinder head design for improved power at higher revs, unlike the brand's top competition models which rely on 4 valves per cylinder for greater low- and mid-range punch.

The engine of the YZ250F retains a 5-valve cylinder head design for improved power at higher revs.

Even lighter
The revised clutch is similar in design to the YZ450F. Notable improvements include a shorter lever for quicker response, a sturdier drive gear, an additional friction plate for more endurance and softer springs for easier shifts.

In other news, the 2009 model is lighter overall and the chassis is improved thanks to these key elements:

· A lightweight, tapered, aluminum swingarm providing greater torsional flexibility for a light handling feel on bumpy trails;

· A revised rear hub design featuring a third bearing for increased rigidity and durability;

· A hollow rear wheel axle;

· A lighter aluminum front brake hose holder;

· A forged aluminum lower triple clamp that reduces weight and optimizes the overall rigidity balance of the front fork. An additional set of holes for the handlebar holders have been added, offering a 30-mm adjustment range;

· A narrower seat offering more grip in strategic areas for improved rider mobility and stability. With the dual-density foam, the more you apply pressure, the firmer the seat gets.

Despite facing some intense competition (KX-F, CR-F and KTM, among other rivals), the Yamaha YZ250F will certainly go back to its winning ways this summer. The chassis is more capable than ever and the machine proves to be safe and easy to ride for enthusiasts, no matter how experienced they are.


Photo Credit : Yamaha