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

The shorter intake design produces a faster beat to the pressure wave which optimises volumetric efficiency, while a longer intake leads to a slower pressure wave beat. Yamaha’s designers have succeeded in creating YCC-I, a unique new electronically-controlled intake system which ensures optimum performance at both low and high engine speeds.

The YCC-I system features electronically-controlled variable intake funnels, and is the first electronically-controlled motor-drive system ever used on a production motorcycle. This unique system features four lightweight plastic resin funnels which are divided into an upper and a lower section, and while fully connected, the two sections create a funnel of 140mm in length.

However, when the new R1 engine reaches a specific rpm – and the throttle opening also exceeds a certain level – the upper and lower funnels separate to create a shorter intake funnel of 65mm in length. The pre-programmed separation of all intake four funnels is simultaneous, and is driven by an electronically-controlled servo motor.

In effect, the new R1 engine is a true ‘no compromise’ design which is able to deliver highly efficient performance in a wide range of riding conditions. Riding around town at lower rpm, the 998cc engine is operating with its long 140mm intakes, which give strong torque and excellent throttle response. And once the rider increases the engine speed and throttle opening on fast highways or when circuit riding, the intake length is instantaneously reduced to 65mm, allowing the engine to reach its full potential.

Another advantage of the new YCC-I system is that its structure is minimal and simple, giving optimal reliability combined with low weight.

New YCC-T (Yamaha Chip Controlled Throttle)

In 2002 the R1’s fuel injection featured an innovative suction-piston system, and the fourth-generation 2004 R1’s fuel injection benefited from an electromotor driven sub-throttle valve. Now, in the never-ending quest for ever-greater levels of performance from the fuel-injected R1 engine, we have focused our attention on intake air volume control.

For 2007 the all-new R1 is equipped with our widely-acclaimed YCC-T electronic throttle which, combined with the new YCC-I and advanced fuel injection systems, helps to achieve outstanding torque and instant throttle response, from idle right through to the red line.

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