Yamaha YZFR1Y(C) 2009 Service Manual page 14

Aims and advantages of using YCC-I system
• Improvement of the engine power characteristics
The high power design in all ranges is now provided by having both two features of the short
intake function to ensure the power at the high speed revolution of engine, and the long intake
function to ensure the power in the practical use range.
• Intake pipe length switching control using the motor
The intake pipe length switching operation in a minute time is now available by means of the motor
drive using the electronic control. The smooth power characteristic is provided, which does not let
an operator feel the switching action by the optimization of its switching revolution number and the
most suitable application of engine at the time of changing the revolution.
A. Down position (long intake)
(Low rpm to Mid rpm)
B. Up position (short intake)
(High rpm)
1-5
FEATURES