An apparatus and system are disclosed for automatic centrifugal engagement of a clutch incorporating a friction disk that expands when rotated above a threshold speed. The apparatus may include a clutch basket, a clutch pack capable of coupling the clutch basket with a center clutch, a pressure plate that may be easily adjusted to create a gap between the pressure plate and the clutch pack and an expanding friction disk assembly that may take the place of one or more friction disks. The assembly expands under centrifugal force to provide automatic engagement of the clutch. A mechanism is provided to manually override the automatic engagement of the clutch with a clutch lever and with improved operational performance of the clutch lever versus previous automatic clutch systems.