Bearings would be required to support the axle of the bicycle crank and to support the shaft that transfers motion from the smaller gear to the large bucket wheel (constraining radial motion). These bearings must do their job of supporting these moving parts while providing a minimum of frictional resistance to the turning parts. Although our diagram shows only vertical forces being applied, axial motion must be constrained because operation of the device would cause vibration and shimmy. Bearings also needed to keep the wheels and gears in place on the shafts, and to keep the entire system from wobbling side-to-side.