Tool of the Week #7 – Spoke Wrenches and Truing Stands


This week, we’re discussing spoke wrenches and truing stands. Both are integral tools to making and keeping your bicycle wheels running round and straight!

 

Spoke Wrenches

Spoke wrenches are used during the building and repair of bicycle wheels to adjust the tension of the wheel’s spokes. Spokes are connected on one end to the wheel’s hub and on the other end to the spoke nipple. The nipple and spoke are both threaded, so the spoke and nipple can be screwed together to secure them just like a nut (the nipple) and bolt (the spoke). Spoke wrenches are sometimes called nipple wrenches, as it’s actually the spoke nipples (the “nuts”) that are turned to adjust the tension of the spokes.

 

Spoke wrenches, just like other types of wrenches, come in different sizes. For the Park Tool wrenches used in the Bike Kitchen, the size is visible based on the colour of the wrench.

Black are for 0.127” (3.23mm) nipples.
Green are for 0.130” (3.30mm) nipples.
Red are for 0.136” (3.45mm) nipples.
Blue wrenches are for 0.156” (3.96mm) spoke nipples.

By adjusting the spoke tension using spoke wrenches, a wheel that is wobbly or “out of true” can be brought back into alignment. When a wheel is out of true, spokes on one side or section may be more tight than those on the other side or another section, resulting in part of the wheel being pulled out in one direction or more. Out of true wheels are not as strong as perfectly true wheels, and can make it difficult to perfectly adjust the brakes due to the wobble.  Sometimes the rim is bent or unable to be trued and must be replaced.

 

We’re not going to get into the nitty-gritty of wheel truing here, but here’s a quick overview to get you started.

There are four aspects of wheel truing:

1. Lateral true: This is the side-to-side wobble that can be seen when the wheel spins.

2. Radial true: This is the up-down type of wobble from a wheel that is not perfectly round. It can be felt as a bump for each wheel rotation when the bike is ridden.

3. “Dish” or rim centering: This is how centered the wheel is in relation to the hub.

4. Tension: This is the tightness of the spokes. It can be tested by plucking each spoke: the front wheel spokes should all sound the same, while the rear wheel spokes should sound the same as those on the same side.

 

Fixing an out of true wheel is typically done using a truing stand. The truing stand holds the wheel steady while being trued and makes is easier to gauge in which way(s) the wheel is out of alignment. Before putting a wheel in the stand, the wheel is removed from the bicycle and the tire and tube are removed from the wheel so it’s just the hub, spokes and rim. See the previous post on tire levers for tips on removing tires!

When truing, it’s important to remember that the spokes and nipples have a standard right-hand thread, but you are looking at the nipple from the bottom. This means that turning the spoke wrench on a spoke clockwise loosens it while counter-clockwise tightens it.

If you noticed your wheel is out of true in one or more of the ways described above, come into the Bike Kitchen. The mechanics can show you in more detail how to true your wheel to get your wheel rolling straight and strong again!

 

*Thanks to howstuffworks.com for the photo of spoke anatomy

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