a lightweight centrifugal friction clutch for transmitting torque from an input source to an output shaft , which includes a wheel secured for simultaneous rotation with the output shaft , a clutch band encircling the wheel and secured within a clutch housing rotationally driven by the input source , and a centrifugal mechanism and cam for tightening the clutch band about the wheel for frictional contact and simultaneous rotation therewith . the centrifugal mechanism includes one or more weights positionable on a centrifugal arm , an actuating arm which rotates a cam member , and an adjustment linkage between the two arms . the particular rotational speed at which the clutch engages may be altered by adjusting the tension against a biasing spring that operates against the centrifugal mechanism , by replacing the spring , or by altering the lever action of the centrifugal mechanism by varying the attachment points of the adjustment linkage between the two arms . the clutch housing is sealed by o - rings and filled with oil which dissipates heat to fins on the exterior of the clutch housing . a protective cover encloses the clutch mechanism .