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About six months ago something got caught in the spokes of my back wheel. The wheel was functional, but visibly untrue. I took it home and trued it with a spoke key, continually adjusting the rim brakes and using them to evaluate the straightness of the rim.

A while ago one of my colleagues told me that there's risk that, because I did this without a truing stand, I may have over-tensioned one side of the wheel, rendering it straight but unstable. Is that possible, and could it be unsafe? Are there any other risks to consider when truing wheels without a stand?

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    Using a truing stand doesn't prevent over-tensioning. It's quite common to true a wheel using just the bike frame and brakes for references. The main advantage of the truing stand is that it's faster, when a lot of adjustment is needed. Jun 28 at 22:53
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    Risk of damage to the brake cables with the bike sitting upside down... Jun 29 at 11:52
  • IMO none. Just hold the wheel in the air and spin it. You can see any wobble/runout. A truing stand makes the locations of those point somewhat easier to find - that's all. Dish? Put the wheel on the ground with one point of the rim on the floor and the opposite point against that leg of the stool you're sitting on. Note the height of the rim where it hits the stool let. Flip the wheel over and repeat. If the height of where the rim hits the stool leg is the same, the wheel - if true - is symmetrically dished, assuming the axle is symmetrical. Jun 29 at 15:29
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A truing stand is a tool to speed-up the process. Using one does not stop the operator from doing it wrong.

A good technique can work well enough using a finger pressing lightly on the rim and leaning on the seat stay. Find the high spot, and twiddle the nipples till its less-high. Repeat on other side.

Rim brakes don't work well for me because they move around a bit. I have been known to strap a zip-tie onto the frame and use that as a pointer.

Finally, you can use a tension-meter on the wheel to gauge the spoke tension, or use your ear by tapping each spoke lightly with something metallic. The resulting sound should be ting-ting-ting like the wheel is talking conversationally. If you hear a high-pitched tink or a low twanggg then check that spoke; you can share the load around a bit more evenly in that area of the rim.
You can even find loose/tight spokes while destressing the wheel by squeezing pairs of spokes. Your fingers should be sensitive enough to show "hey this one feels different"

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    Love the formatting!
    – MaplePanda
    Jun 29 at 0:56
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    When I'm building wheels I use the frame, with a steel rule clamped across the fork/seatstays to give me a centring mark and check for lateral deviation. For out-of-round errors a 2nd steel rule (or just a strip of plastic) clamped to the first and barely touching the rim works well
    – Chris H
    Jun 29 at 12:00
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    I've trued wheels this way when brakes are rubbing and I'm away from home, but keep in mind that you have to true a wheel side-to-side (towards left or right brake pad) and up-and-down (towards/away-from the hub) to keep the rim round. If you tighten a single spoke at a time, you're likely to correct a rubbing brake pad, but may make your wheel egg shaped. You can minimize that risk while truing by adjusting three spokes at a time: at the center of the 'lump' there is a spoke that should be tightened/loosened. Turn the two spokes around it in the opposite direction to push and pull the rim.
    – Rich Moss
    Jun 29 at 17:41
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    +1 for the cable-tie tip alone! Jun 30 at 13:20
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There are very great risks in truing wheels, but none of those is related to a truing stand.

If a spoke is on the brink of failure (especially likely on a used wheel of unknown build quality since the spokes may not have been stress relieved initially, but can happen on a new wheel because new spokes can have undetected manufacturing defects that would have been detected if the wheel was used for few thousand kilometers), tightening it with a spoke wrench could break it. If a tensioned spoke breaks, the end shoots out at very great speed. If you have your eye in the path of the flying spoke, it WILL make you blind.

However, this can happen with a truing stand too. Nothing in a truing stand can prevent it. To prevent this from happening, true a wheel with at least the rim tape on, because it will catch the flying spoke end (assuming a high pressure rim tape here, not a low pressure rubber one). Also if you have a tire (which implies you have the rim tape), it will present an even greater barrier for flying spoke ends.

It may also be beneficial to always tension spokes which don't fly towards your face. You can for example use a habit of only tensioning spokes facing down. This may be easier if you have a truing stand.

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    Or invest in a pair of safety goggles for this purpose... Jun 29 at 19:06
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    I'm guessing that there are other parts of one's body that could also make an uncomfortable target (albeit less devastating than losing one's sight). But goggles and care is a good combination (rather than either/or). Jun 30 at 13:22

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