the invention concerns a stator for a line - start electric motor , with a rotor accommodating chamber , in which a rotor is accommodated to be rotatable , and which has accommodating chambers for conducting rods and accommodating chambers for permanent magnets , and with a stator winding comprising several windings , which , during operation of the line - start electric motor under the influence of the rotor , generate a magnetic field with a main axis . in order to increase the efficiency of the line - start electric motor , the rotor accommodating chamber has no constant inner radius , but , in the area of a vertical to the main axis , has a larger inner radius than in the adjacent areas .