Yamaha YZF-R1 - 50th

FOUTH GENERATION YZF-R1 STILL ' THE ONE ' A machine developed from a solid foundation of race winning motorcycles and designed to be the best performing Superbike in the twisties. The focus on this new model is on increased engine and cornering performance. To achieve this goal, Yamaha’s engineers have boosted power by maximising intake and exhaust efficiency and optimised the frame balance by altering the main frame and lengthening the swingarm. The new R1 maintains the same liquid-cooled 4-stroke, DOHC, 40 degree forward-inclined, 4-cylinder and 5-valve fuel injected engine format. But a new-design combustion chamber, high-lift cams and 12.4:1 compression ratio has increased intake/exhaust efficiency for a significant boost in power output. A smoother intake port shape has also increased intake air volume. Max power has been raised by 3bhp to 175bhp at the same rpm level of 12,500 rpm (or 183bhp with ram air effect).
Source: frasermotorcycles.com.au