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Wheel True

The lateral and radial accuracy of a wheel — how straight and round it runs as it spins.

Published June 9, 2026

Definition

Trueness is the measure of how accurately a bicycle wheel runs in a straight plane and a perfect circle as it rotates. A wheel is described as true when it has no lateral (side-to-side) wobble and no radial (in-and-out) deviation from a perfect circle. Truing is the process of correcting these deviations by adjusting spoke tension.

Lateral Trueness

Lateral trueness describes how straight the rim runs side-to-side as the wheel spins. A laterally untrue wheel wobbles left and right — visible when spinning the wheel slowly and sighting along the rim. On a bike with rim brakes, a lateral wobble will cause the brake pads to intermittently contact the rim, producing a rhythmic rubbing or pulsing feeling at the lever.

Lateral deviation is corrected by tightening spokes on the side opposite the wobble and loosening spokes on the same side, drawing the rim toward the tight side.

Radial Trueness

Radial trueness describes how round the rim is — whether it stays at a consistent distance from the hub center through a full rotation. A radially untrue wheel has a hop or flat spot that causes the bike to bob up and down at speed.

Radial hops are corrected by tightening spokes in the high spot to pull the rim inward, and loosening spokes in surrounding areas to allow the rim to drop. Radial truing is generally more difficult than lateral truing and is less commonly needed.

How to True a Wheel

Wheels are trued in a truing stand — a jig that holds the wheel and provides a reference gauge to measure deviation. In the field, the bike frame or fork legs serve as a rough reference.

The basic process: spin the wheel slowly and identify the deviation, then make small adjustments (quarter turns or less) to the relevant spokes, alternating sides to maintain dish. Check tension regularly — a properly trued wheel should also have even spoke tension throughout.

Spoke nipples tighten clockwise when viewed from the nipple end (at the rim), which is the opposite of most fasteners.

When Wheels Go Out of True

Wheels lose trueness in two ways: gradually through normal use as spokes bed in and relax, or suddenly through an impact — hitting a rock, pothole, or landing badly. Because spokes only ever loosen on their own, new wheels benefit from a follow-up truing after the first few rides once tension has settled. A wheel that repeatedly goes out of true despite truing — absent any obvious impact — usually has a broken spoke, a cracked rim, or severely uneven spoke tension from a poor original build.

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