Yamaha’s all-new 189 bhp, US$11,600 YZF-R1 Supersport

The most technologically-advanced R-series engine

The new fifth-generation R1 is powered by the most powerful and the most technologically-advanced engine ever featured on a production Yamaha. Its liquid-cooled 4-stroke in-line four-cylinder engine runs with the same bore x stroke dimensions of 77 x 53.6mm as the 2006 model, but that is where the similarity ends.

G.E.N.I.C.H. – Yamaha’s advanced electronic control technologies

The all-new R1 engine benefits from sophisticated new technology that has been developed through Yamaha’s G.E.N.I.C.H. engineering concept. The aim of the G.E.N.I.C.H. programme is to develop unique new electronic control technologies that will offer even higher levels of performance, while also strengthening the close relationship between the rider and the machine.

New YCC-I (Yamaha Chip Controlled Intake)

The latest and most innovative product of the Yamaha G.E.N.I.C.H. engineering concept is YCC-I, which makes its debut on the 2007 YZF-R1, and is the first-ever electronically-controlled motor-driven variable intake on a production motorcycle. For over fifty years Yamaha have been at the forefront in the development of exciting new motorcycle technology, and the new YCC-I Yamaha Chip Controlled Intake system represents one of the most significant developments in electronic control ever seen in the supersport engine sector.

The intake passage length on an engine is designed to ensure the highest volumetric efficiency in the most commonly used rpm band for that particular powerplant. Generally speaking, a long intake passage and funnel tends to deliver stronger low to mid-range performance, and conversely a shorter intake passage and funnel is typically better for high rpm applications.

During the intake process on any four-stroke engine, the downwards motion of the piston creates negative pressure in the intake passage, which causes a pressure difference with the air and its natural inertia. This pressure difference causes a reverse reaction in the direction of the intake valve in a function known as ‘inertial charging’, and this phenomenon increases the engine’s volumetric efficiency.

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