Abstract: A CVT drive system comprising a sheave axially moveable along a first shaft and having a radially extending surface, a sheave fixed to the first shaft, the fixed sheave cooperatively disposed with the moveable sheave to engage a belt therebetween, the first shaft engagable with an engine, a back plate attached to the first shaft having a radial surface, the back plate engaged with the moveable sheave for locked rotation while allowing a relative axial movement, an inertia member radially moveable upon the radially extending surface and the radial surface upon rotation of the moveable sheave, the inertia member is temporarily disengagable from the radial surface and from the radially extending surface, a first spring resisting axial movement of the moveable sheave toward the fixed sheave along the first shaft, and a sleeve member disposed between the moveable sheave and the fixed sheave, the sleeve member rotatable with the belt.