The main clutch is an advanced kind of centrifugal clutch and is typically mounted to the output close of the motor crankshaft. The clutch has two sheave faces; one that is laterally fixed (stationary sheave), and one which can transfer out and in to interact the belt (moveable sheave). https://cvt11864.blogzet.com/not-known-details-about-gearbox-cvt-47184294