Wheel Offsets
Ollie
Last Update 2 years ago
What is Offset?
Offset is simply the distance from the hub mounting surface to the centre of the wheel. In other words, Offset = Measured Backspace – Calculated Wheel Centre Distance.
Zero Offset
Your wheel centre line is in sync - or in-line - with the wheel hub mounting surface.
Positive Offset (Insets)
There is a greater distance between your wheel's centre line and the hub mounting surface, so your tyre will sit deeper on your axle and under the wheel arch.
Positive offset cause the wheels on either side of your vehicle to sit closer together. Most OEM and non-OEM wheels have a positive offset.
Negative Offsets (Outsets)
A negative offset is when the top surface of the hub mount sits on the other outer side of your wheel's centreline.
Negative wheel offsets, cause the wheels on either side of your vehicle to sit further apart on the axle, towards the suspension, so the wheels protrude slightly from the wheel well.
How to Measure Offset
Sometimes the offset isn’t printed on the wheel, or it might be printed in digits that are difficult to read or impossible to decode. No worries; it’s easy to measure offset yourself.Technically, offset is the distance from the hub mounting flange to the centerline of the wheel between the mounting beads. Since you can’t measure between the beads with the tire on the wheel, here’s an easy way to find offset by measuring from the tire sidewall.
1. Lay the wheel/tyre assembly on the floor and place a straight edge across the tire.
2. Measure the distance from the floor to the straight edge and divide by two. That calculates the centerline of the wheel. If the centerline number is smaller than the hub measurement, offset is positive; if it is larger, offset is negative.
3. Measure the distance from the floor to the straight edge and divide by two. That calculates the centerline of the wheel. If the centerline number is smaller than the hub measurement, offset is positive; if it is larger, offset is negative.
4. Measure the distance from the floor to the straight edge and write down that number.
5. Divide that number by two to calculate the centerline of the wheel.
6. Now measure from the hub flange to the straight edge.
7. Subtract the smaller number from the larger number. That gives you the offset of the wheel. If the centerline number is smaller than the hub measurement, offset is positive.