The clutch is device which is used engage and disengage power from a engine.A engine will keep rotating even when we are idling or coasting or while running
If there is no such device called Clutch then in order in slow down or stop , we must switch of the engine.. but this is a inefficent process
Hence a clutch is a device which is used to disengage power from engine , when we are standing still , now the engine can move rotate freely(idling) as there is no load.
Clutches in motor bikes
Motor bikes use a manual clutch similar a cars clutch the principle is similar.
Whats happens when u try to stop a rotating object using ur hands, yes our hands try to rotate with the rotating element this is due to friction.
This is the principle used in a clutch . It consists of friction surfaces enganging together to transmit power. When the clutch is pressed the friction surfces move away from each other hence power is not transmitted
Most bike use multi plate clutch , if its a wet multi plate the the whole clutch is immersed in transmission oil.
- Rekluse clutch used in Harley davidson,Slipper clutch (available in KTM 200,390)
Motor scooters clutch
They use a automatic clutch mostly of centrifugal type. the working principle is very simple.
Tie a heavy object or stone to one end of thread and rotate it. The object will rotate as shown in fig.
What will happen if u increase speed of rotation , yes the radius of rotation increases.and if speed is reduced the rotation radius also reduces.
This principle is used to engage the centrifugal clutch .similar to the above example , a rotating mass or the brake shoe which expands is used here.
Working is simple ,while we are idling the engine RPM is very less . so the Rotating masses rotate in lesser radius , so power is not transmitted to wheels . When speed increases the centrifugal force causes the rotating masses to expand and comes in contact with wheel hub.hence power is transmitted
- Centrifugal clutch and CVT together experience transmission loss so only they are not used in Motor bikes.They are used in motor scooters due to their simplicity