The first clutch is a complicated method of centrifugal clutch and is often mounted to the output stop with the motor crankshaft. The clutch has two sheave faces; one that is laterally set (stationary sheave), and one that can shift out and in to engage the belt (moveable sheave). https://gearbox-cvt79011.wizzardsblog.com/32288202/the-5-second-trick-for-gearbox-cvt