A uniform clamp actuated shift infinitely variable transmission system is provided that includes a drive clutch and a driven clutch. Both the drive clutch and the driven clutch include torque sensitive assemblies. In particular, the drive clutch includes a drive torque sensitive assembly that is in operational communication with a movable drive sheave member of the drive clutch. The drive torque sensitive assembly is configured to move the movable drive sheave member in relation to a fixed drive sheave member based at least on torque applied to the drive torque sensitive assembly. The driven clutch includes a driven torque sensitive assembly that is in operational communication with a movable driven sheave member of the driven clutch. The driven torque sensitive assembly is configured to move the movable driven sheave member in relation to a fixed driven sheave member based at least on torque applied to the driven torque sensitive assembly.

A uniform clamp actuated shift infinitely variable transmission system is provided that includes a drive clutch and a driven clutch. Both the drive clutch and the driven clutch include torque sensitive assemblies. In particular, the drive clutch includes a drive torque sensitive assembly that is in operational communication with a movable drive sheave member of the drive clutch. The drive torque sensitive assembly is configured to move the movable drive sheave member in relation to a fixed drive sheave member based at least on torque applied to the drive torque sensitive assembly. The driven clutch includes a driven torque sensitive assembly that is in operational communication with a movable driven sheave member of the driven clutch. The driven torque sensitive assembly is configured to move the movable driven sheave member in relation to a fixed driven sheave member based at least on torque applied to the driven torque sensitive assembly.

A variable speed belt drive system having a driving pulley, a V-belt, and a driven pulley connected to the driving pulley with the V-belt. The driven pulley includes a pulley shaft rotatable about a pulley axis, an inboard pulley-half having a first contact surface that is inclined relative to the axis of the pulley shaft that defines a first belt-contacting wall of driven pulley, wherein the first contact surface is fixed relative to the pulley shaft. The driven pulley has an outboard pulley-half having a second contact surface that is opposite the first contact surface and that is inclined relative to the axis of the pulley shaft, the outboard pulley-half being movable relative the inboard pulley-half such that the second contact surface is moveable relative to the driven pulley shaft. The inboard pulley-half is connected to the outboard pulley-half with two or more tension struts.