In a method of mounting attachment parts to an electric machine, a rotor of the electric machine is non-rotatably supported in a bearing device. A stator of the electric machine is detachably secured in a predefined first installation position by a clamping device, and a first attachment part is mounted to the stator. The clamping device is then released, and the electric machine is operated as motor for a time period sufficient for the stator to rotate in relation to the rotor until reaching a second installation position. The stator is secured by the clamping device in the second installation position, and a second attachment part is mounted to the stator.