An electric motor includes a stator and a rotor having a rotor shaft with a longitudinal axis. The rotor shaft has a locating groove formed substantially continuously around the rotor shaft. The locating groove has a base and a pair of opposing sidewalls. The base is arranged substantially parallel to the axis of rotation. The pair of opposing sidewalls extends from the base wall substantially perpendicular to the axis of rotation. The motor includes a thrust system mounted on the rotor shaft, and a locator disposed in the groove for locating the thrust system in a predetermined position along the rotor shaft.