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I have a v-brake mounted on my bike. I can feel some stopping from the pads. If i spin the wheel, it stops because of one of the pads rubbing. I can't find a setting where one of the pads doesn't touch the rim. When I put less tension, the pads don't touch the wheel, but in that setting, the tension is too low. I have played with the pad positions. I have played with brake tension. I have even played with spring tension, in order to adjust the brake movement. Both arms move at the same time.

What can this be? Bent rim?

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  • If the wheel is out of true that would definitely cause it. Do you know the wheel is true? – Carey Gregory Jun 1 '13 at 2:37
  • If the wheel rubs on the brakes and stops when you spin it, it is out of true. – Scott Hillson Jun 1 '13 at 4:41
  • how do i know if the wheel is true? – danieltorres Jun 1 '13 at 11:09
  • Using the valve as a reference does the wheel stop in the same place every time? Does it rub constantly around the entire wheel? – mikes Jun 1 '13 at 22:20
  • @mikes i can hear it rubbing with a kind of a delay, which leads me to think that it might be true. Is it easy for a non-expert to correct this issue? I've seen one or two videos on the subject. Can i go for it? – danieltorres Jun 2 '13 at 0:11
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Your wheel is out of true, this happens under normal conditions as spokes stretch.

You're going to need a truing stand, some lubricant, and a a spoke wrench. (I've heard you can use zip-ties attached to each side of your wheel fork, facing inward, then cut to size, but I don't think this makes for very accurate measurements.) Most bike shops I've worked with will let you borrow their stand for a few minutes. If not, find a co-op or make new friends.

Put your wheel in the truing stand and start by lubricating each spoke nipple. Once lubricated, use the guides on the stand to determine where the wheel has been skewed to one side. Select a spoke at that site, opposite the side of the skew, and tighten the spoke to pull the wheel away from the truing stand guides. Also lightly tighten spokes that are next to this initial position (but still on the same side) to even the strain on your spokes.

A word on which way to tighten the spoke - remember that you are probably going to view the spoke nipple from across the wheel axle - therefore the directions to turn for tightening is reversed from normal. Also, it is preferable to tighten spokes rather than to loosen them, as the main cause of a wheel being out of true is/are a stretched spoke(s). Even so, be aware that spokes can occasionally be over-tightened, it may be better to loosen a spoke to compensate for a wheel pulling to that side. As you tighten spokes, you will hear lots of popping/straining sounds of the metal. This is normal, and may continue for a few miles of riding after adjustment.

As you adjust areas of the wheel that are out of true, slowly tighten the guides on the truing stand to find the next area that needs adjustment. Also be aware of the differences between getting the wheel perfectly in true, as opposed to good enough in true. You can spend an hour truing a wheel, but it probably won't be much better than it was 10-15 minutes in.

Re-install you wheel on your bike and adjust your brakes as normal.

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  • as i don't have a truing stand, i will try this with the wheel on the bike. thank you – danieltorres Jun 3 '13 at 16:59
  • Also, you could take it to a shop and have them true it, probably for about $20 bucks give or take. It's a good skill to learn, but if you're not equipped with all the tools, a shop isn't a bad way to go. – Benzo Jun 5 '13 at 13:19
  • For minor adjustments truing stand and/or zip ties are not needed. Just spin the wheel and observe where it gets closer to or farther away from the brake pads. – Daniel R Hicks Jun 5 '13 at 16:17
  • I made it. Without the truing stand. Now it doesn't rub on the pads. – danieltorres Jun 5 '13 at 22:01
  • I personally prefer to be more precise when adjusting anything on my bike. The idea of adjusting spokes where the wheel hits the brake is depended on the brakes aligning symmetrically on either side of the wheel... which is usually done by how close they are to the wheel... it's a viscous cycle.Probably is better than nothing in practice though. – Jonathan Jun 7 '13 at 5:49

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