A brushless motor includes a stator having stator core and winding teeth evenly distributed on the stator core; and a rotor rotatably disposed within the stator with the winding teeth facing the rotor, where the rotor has a rotor core and magnets evenly distributed around the rotor core. A first symmetry axis is defined passing through a center of a one of the magnets to a center of the rotor, and a second symmetry axis is defined passing between adjacent magnets to the center of the rotor. A first distance between the outer surface of the rotor to a surface of a winding tooth when the first axis is aligned with the winding tooth is smaller than a second distance between the outer surface of the rotor to the surface of the winding tooth when the second axis is aligned with the winding tooth.