Abstract: A cone drive, high output speed reducer, having a low clearance for low profile applications. An input shaft drives a helical idler pinion which in turn drives two other helical idler pinions. The two other idler pinions are each mounted on a separate shaft carrying a cone drive worm. The two worm shafts turn in unison, and the worms are each meshed with a separate worm gear. The two worm gears are operatively mounted on an output shaft. One of the helical idler pinions is provided with an adjustment means for equalizing the load sharing. That is, to provide equal loads on each of the helical pinions for load sharing throughout the twin drive gearing units of the speed reducer. The speed reducer may be provided with either an air cooling system or a water cooling system.