Slippage generally occurs at a high engine speed when the engine is delivering the greatest torque.
Slippage causes lower efficiency, loss of power, and rapid wear of the clutch friction surfaces.
Over a period of operation, extended engaging and disengaging of the surfaces will cause a normal amount of wear. If the surfaces are rough, wear will be excessive. Do not engage the clutch while the engine is racing. It may cause excessive wear, and it will strain the entire drive system. When an engine is overloaded, torque may be increased to such an extent that slippage will occur.