Abstract: A variable speed control for closed loop hydrostatic drive has a variable displacement, pressure compensated, hydraulic piston pump of nominal capacity and a hydraulic motor of similar capacity with reversible inlet and outlet ports, connected to the pump inlet and outlet ports to operate in a closed loop for bidirectional rotation according to the pressure differential across the motor ports, and a proportional control valve, having a nominal flow capacity of no more than one-tenth the given pump output capacity, interposed between the pump and the motor to restrict and regulate oil flow through the relatively low pressure side of the loop for smooth, slow speed motor rotation, with a controller, connected to control the proportional valve for selection of a flow rate within its nominal capacity.