What Does Backspacing Mean?

Backspacing is an older system of measurement to determine how deep the mounting pad is located in the wheel. Correct backspacing allows enough room for the suspension, brake, and steering systems to operate without interference from the wheel.

What does backspacing mean on a wheel?

Backspace is the distance from a wheel's mounting surface to the back edge of the wheel in inches. By "back" we mean the brake side of the wheel. Offset measures the distance from the mounting surface of the wheel to the centerline of the wheel, and it is often indicated in millimeters.

How do you determine backspacing?

Take a straight edge and lay it diagonally across the inboard flange of the wheel. Take a tape measure and measure the distance from where the straight edge contacts the inboard flange to the hub mounting pad of the wheel. This measurement is backspace. The above photo shows three wheels with 2",3", & 4" backspace.