Abstract: A method is provided for balancing a disc brake rotor having a first annular friction plate, a second annular friction plate, and a core gap. The first annular friction plate includes a first circumferential surface. The second annular friction plate includes a second circumferential surface. Respective regions are determined for removing material within the first circumferential surface and the second circumferential surface for balancing the disc brake rotor if the disc brake rotor is out of balance. A rotary straddle cutting tool is aligned with respective regions of the first circumferential surface and the second circumferential surface. Material is cut from the respective regions of the first circumferential surface and the second circumferential surface with the rotary straddle cutting tool. Cutting material from the respective regions includes removing material within the width of the first circumferential surface and the second circumferential surface.