Yamaha YZF-R25 is surely and interesting 250cc bike in its category. It features 35.5 horsepower at high-revving engine of 12,000RPM. The engine is using the offset cylinder to maximise the power delivery to the crankshaft as the connnecting rod will be in straight position when the piston hits BDC (bottom dead center). Also included is the proven DiASil alloy cylinder that minimises friction to the wall of the cylinder from the piston.
Forged aluminium piston ensures the total mass of the piston is low (thus making it lightweight) and at the same time, tough enough to handle the 35.5hp. The connecting rod are carburized which mean it is carbon-hardened to enables it to be strong.
Of course, the engine is fuel-injected to ensures the accurate fuel metering and able to maxes out the power it can.
It is a truly beautiful bike with a great engine. Check out the video embed below: