Monday, April 7, 2008

Wheel Truing, it's easier than you think!

After a hard ride or race, you may find that your wheels aren't running as straight as they used to. As long as there isn't any rim damage, this is an easy fix and is a really handy skill to have under your belt. This article is for lateral (wobbling side to side) truing and doesn't cover radial truing or centering the rim over the hub.

Anatomy of the wheel

Understanding the anatomy of the wheel makes wheel repairs easy. The wheel consists of the hub (central moving part), rim (the outer ring), spokes (the straight, wire-like parts that hold the wheel up) and the nipples (small threaded part used to connect the spokes to the rim). The spokes hook onto the hubs and are laced in a certain pattern onto the rim. There are spokes on the left and right hand sides of the wheel which need to be balanced in tension to ensure a true wheel. The spoke tips are put through the holes in the rim and the nipples screw on top to create spoke tension. If a wheel is out of true, the spoke tension on either side is uneven, pulling it out of alignment.

Tools Of The Trade:

  • spoke key (use one that fits your spoke nipples properly. It should be the smallest size that fits on the nipple)
  • matchsticks and blue tack (or a truing stand if you can get your hands on one)
  • tyre leavers

DIY truing stand

To true a wheel you need to see exactly how far the wheel is moving side to side. You can buy a truing stand or you can improvise by blue tacking match sticks to your fork legs or frame tubing next to the rim.

Get Started!

It isn't completely necessary but I find it easier to true the wheel with the tyre off. Put the wheel in the frame/fork ready to be trued.

With your DIY truing stand, move the matchsticks close to the rim on both sides so that one of them touches it at the peak of a wobble. You then need to find the central point of each wobble as they usually cover a couple of inches each.

Once you've found the central point, there should be a corresponding spoke on the other side. If the wheel wobbles to the right, tighten the central spoke that is on the left side as this will pull the rim back into alignment. Keep in mind that one spoke will pull across the value of about six. Always work out the biggest wobble first and then progress to the minor problems.

To tighten, put the spoke key on the nipple and and turn clockwise (when viwed from above) about one third of the way. The direction you turn the nipple on each spoke is the same regardless on whether it is a left or right hand spoke. How much you tighten each spoke depends on how severe the wobble is, as the smaller the movement, the less you will need to tighten.

Continue to spin the wheel to find and correct any wobbles remembering to work on both sides. The wheel is true when it moves no more than one milimeter. Sometimes when putting the tyre back on, the bead doesn't sit perfectly making it look out of true; this is why I take the tyre off when truing so I can get a more accurate alignment.

Your wheel should now be straighter, stronger and more responsive than ever before!

1 comment:

  1. well that just saved me 15 bucks! wheel truing is way easier than i thought.