A rotor for an electric machine having a number of poles includes a shaft that extends along a portion of an axis and defines an outer surface. A first core portion is formed as a single inseparable component and includes a first portion that extends from the outer surface to a first outside diameter to define a first thickness, and a second portion spaced axially from the first portion that includes a reduced back portion that extends from an inside diameter to the first outside diameter to define a second thickness that is less than the first thickness. A second core portion is connected to the first core portion and includes a second outside diameter that is substantially the same as the first outside diameter.