trueing

Trueing is the act of making an object true, meaning aligned to a reference axis, straight, and free of wobble. The term is used in several crafts, including bicycle maintenance, metalworking, and woodworking, where precise alignment is essential for performance and safety.

In bicycle wheels, truing describes adjusting spoke tensions to bring the wheel into true rotation. Lateral true fixes side-to-side wobble, while radial true corrects hops along the rim. A true wheel spins smoothly and remains centered in the frame and brake track. Common tools include a truing stand or a rim as a reference, a spoke wrench, and a dial gauge or tensiometer to measure runout and tension. The process starts by spinning the wheel to identify deviations, marking high and low spots, and then turning spoke nipples in small increments, typically a quarter-turn. To correct lateral misalignment, spokes are tightened on the side opposite the deviation and loosened on the same side, repeating until the rim sits evenly between the brake pads. Radial corrections involve adjusting tensions around the affected area to raise or lower the rim, again in small steps. After each adjustment, re-check with the gauge and aim for even overall spoke tension to preserve wheel dish and strength. Severe misalignment, damaged rims, spokes, or hubs may require professional repair.

Other uses of trueing include dressing or truing grinding wheels and aligning other rotating tools or components to ensure smooth, accurate rotation. In these contexts, truing similarly involves removing irregularities so the part or tool rotates true to its axis.