a variable speed drive clutch of the type including a drive shaft , a driven or output shaft , a drive sheave on the drive shaft , a driven sheave on the driven shaft , and a drive belt for drivably interconnecting the drive sheave to the driven sheave . the drive sheave includes a fixed half and an axially slideable half . the slideable half defines a housing in which a support or spider for supporting flyweights is mounted . the flyweights move radially outward and inwardly , from a given radius at any given instant , in response to increasing and decreasing rotating speeds , respectively , of the drive shaft . cam rollers associated with the flyweights ride on cam surfaces on the slideable sheave half and cause the slideable sheave half to move axially away from the fixed sheave half , when the flyweights move radially inwardly , and towards the fixed sheave half when the flyweights move radially outwardly . the invention includes a non - circular , outer periphery for the drive shaft and bearing members are secured to the said housing and have the same inner peripheral shape as the outer periphery of the drive shaft so that rotation of the drive shaft is imparted directly to the slideable sheave half while , at the same time , the movable sheave half slides along the drive shaft in response to varying speeds of the drive shaft .