A rotor system comprising a driveshaft; at least one motor for providing rotational energy for the driveshaft; an overrunning clutch connected to the motor and disposed around the driveshaft, wherein the overrunning clutch is rotated by the at least one motor; and a pump assembly associated with the at least one motor, the pump assembly comprising a large bore through which the driveshaft passes such that the pump assembly is arranged concentric to the driveshaft, the pump assembly further comprising a gerotor pump comprising inner and outer gerotor pump gears, wherein an inner bore of the gerotor pump engages and is driven by the overrunning clutch; and a cover disposed over the gerotor pump for providing a sump for the gerotor pump.