After the recent introduction of the 2015 Kawasaki Ninja 250 that feature one defining parts that makes it interesting, the Assist and Slipper Clutch system, many were thinking how it works actually. There are two parts of the Assist and Slipper clutch that is the Assist cam and Slipper cam. As you can see on the picture above, the Assist cam is in light green and the Slipper cam is in dark green. Assist cam operates in normal operation to deliver the engine power to the transmission. The Assist cam have self-servo mechanism, so it will help the rider to feel lighter clutch operation.
Slipper cam comes into action when the rear tyre is experiencing excessive braking or accidental gear drops that makes the tyre rotates faster than the clutch itself, so, the Slipper clutch will separates the clutch hub and operating plate apart. You’ll will feel less engine braking from the tyre since the rotation from the tyre is cut by the Slipper cam. For racing bikes with slipper clutch, there is a setting where you can set how much engine braking you want before the Slipper cam comes into action.