Spoke Wheel Truing by Brad

Technical info not specific to a particular mfr.
Respond to existing topics with questions or comments.
Post Reply
User avatar
Site Admin
Posts: 1215
Joined: May 02, 2016

Spoke Wheel Truing by Brad

Post by 4Strokes » Sun Jun 19, 2016 7:12 pm

Truing spoke wheels is really just a process of averaging out errors. No wheel needs to be absolutely perfect, and trying to make a wheel that way with a dial gauge will only lead to undue stress. Remember the wheel isn't what contacts the road, and the tire will cancel out small wheel errors while bringing its own set of small errors to the game. With this in mind, good wheelwrights will simply use a surface gauge to check visually for a wheel's bumps and wiggles and then, using a spoke wrench, make the rim run as round as possible.

Place the wheel on a truing stand or take an axle and clamp it in a vice so that the wheel will be horizontal (the axle is vertical)(use axle nuts to clamp on so you don't damage threads) when placed on it. Go around the wheel with a spoke wrench and put a little tension on each spoke. Next, put the surface gauge in position and give the wheel a spin. The loose-laced wheel will wiggle in one of three ways: It will roll from side to side, it will have either a hump or dip, or once the other problems are addressed, the entire rim may sit either too high or low, relative to the hub. Since side-to-side motion (which is an up-and-down motion if the wheel is positioned horizontally on the axle) is the easiest to remedy, start by finding the center point of the twist. Spokes will pull the rim sideways when they are tightened so tighten the spokes that would pull in the opposite direction as the twist. For example, if the rim is high in one section (assuming it's on the stand horizontally), tighten the spokes on the bottom side of the rim. Do just the opposite for low sections. Only turn the nipples in the center of the high point one or two of the flat sides and nipples at the outside of the imperfection one or no flats, depending on the severity of the side-to-side roll. Several small adjustments may be necessary to fix the problem.

If the rim has a hump (a place where it rises away from the axle) in one section, tighten the spokes at the center of the hump on both the top and bottom of the rim. Dips usually occur when the spokes in a section are too tight, and loosening the top and bottom spokes slightly, should improve things.

To determine if the entire rim is too high on one side or the other, the distance between the edge of the rim and the hub needs to be measured on both sides. Place a straightedge across the top of the hub or the rim, whichever is higher (the Classic's hub was higher in our case) and measure the distance from the edge of the hub (or if it is not symmetrical, the flange) to the edge of the rim. Flip the wheel in the stand and repeat the process. If the difference between the sides is 1/16 of an inch or greater, the entire wheel needs to be adjusted. Slightly tighten all the spokes on the side with the greatest gap and slightly loosen the spokes on the side with the least gap. Now go back to measure the differences. Once the difference is less than 1/16 of an inch, double-check to make sure the wheel is true. Some minor adjustments may be necessary.

Credits: Wheel Truing article written and submitted by Brad. Edited and published by 4Strokes.com.

Post Reply