Wheel Runout

Lateral runout is side-to-side movement; radial runout is up-and-down movement. It is measured with a dial gauge while the wheel is turned slowly. Bent rims, damaged hubs or tyres that are not seated properly can cause it. Matching the tyre to the wheel by rotating it on the rim can sometimes reduce radial runout.

If the rim or tyre is not perfectly round or true, its edge moves as it rotates, causing vibration.

Balancing cannot fix runout; the cause must be found and corrected. A wheel that hit a kerb or pothole hard should be checked for runout and cracks.