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I find it hard to tighten the hexagonal bolt of a v-brake pad without turning the whole pad out of position. I need to hold it in place somehow; I've tried with a big adjustable wrench, but it's still difficult (doesn't fit very well, and the pad is flexy). Why isn't a small part of the pad body hexagonal so I can hold it with a wrench while tightening?

brake pad

What's the proper way to tighten the pad onto the arm?

  • 3
    The main prerequisite is a rich vocabulary. – Daniel R Hicks Jul 3 at 0:29
  • While it can be a bit tricky, you should be able to tighten the pad without needing a tool to hold the pad with you finger. How tight are you doing them up? Spec is only 6-8Nm (45-60inch pound) – mattnz Jul 3 at 1:17
  • I'm not tightening any more than that. But it's still difficult for me to hold it in place. To keep it from turning I must apply 7Nm torque with my fingers on the pad (a 5cm lever), that's like lifting 14kg with two fingers, isn't it? If I'm replacing all 4 pads on a bike, my fingers will start to hurt. – Robert Lee Jul 3 at 2:06
  • I've seen a tool that holds the pads against the rim (against the force of the springs) for adjusting the cable tension. Would that help? – DavidW Jul 3 at 3:12
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    I pull the brake lever tight and while the pad sits on the flank of the rim the friction is sufficient to tighten the nut. If you use a strap or a helper to hold the lever you can still grip the pad with your free hand. – Carel Jul 3 at 7:26
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I usually just grab the pad with my fingers, and carefully apply torque in the opposite direction of the torque I apply to the screw. The two torques must be roughly equal (very roughly), if you apply too much torque to the pad, you are going to turn it the opposite direction.

It is not enough to grab the pad and try to hold it in place, you have to apply torque proactively to stop the first bit of movement before it happens.

Done right, you can tighten those screws very securely without rotating the pad.

Of course, you need to position the pads properly first, which is easiest to do by applying the brake, adjusting the position of the pads with the brake applied, and fixing their position by tightening the screws with your fingers. You don't really need any torque at that point, as you are just fixing the position. It's when you take out the wrench to tighten the screw for good that you need to apply the counter-torque to the pad with your other hand.


But, of course, a hexagonal surface to grab the pad with a wrench would be nice...

  • Is that after doing a first pass of tightening with the brakes applied to position the pad correctly relative to the rim? I'd mention that to make the answer more complete. – Gabriel C. Jul 5 at 18:45
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    @GabrielC. Right. Position the pads, fix them, tighten them. It's the tightening step that needs the counter-torque. I've added a paragraph on this to the answer now. – cmaster - reinstate monica Jul 5 at 19:15
  • Perfect! Now it's the definitive answer! – Gabriel C. Jul 5 at 19:21
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To tighten a rim-brake pad without it rotating, I've usually clamped down on hard on the brake lever with one hand to hold the pad against the rim, while tightening with the other hand. For that, it may help to have the brake cable temporarily adjusted for severe tightness: tighter than you'd be able to ride with. (Once your pads are secured in place, then adjust the cabling to normal). I've also simply held the pad with my other hand while tightening it, using it as if it were a tool handle. It is not much smaller than the Allen key wrench; you can adequately supply the counter torque this way. There is also a technique of getting it almost tight, such that it still allows a bit of rotation. Then turn it into a position that is slightly off, so then it will rotate into place with the final tightening. Lastly, a tool can be used to supply the opposite torque; for instance, you can restrain the pad between the jaws of a simple spanner wrench.

  • Turning the pad slightly counter-clockwise before tightening it into the right position is a great idea, it worked nicely! Thank you! – Robert Lee Sep 2 at 11:46
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Apply the brakes while tightening the bolt. The friction holds the pad in place and usually adjusts the pad so that it makes good contact with the braking surface. If the pad still turns, try strapping the brake lever in the depressed position so that you can hold the break pad while tightening it.

  • Doesn't work for me, as I want my screws quite a bit tighter than what I can get away with using this method. – cmaster - reinstate monica Jul 3 at 9:28
  • Please take a moment to read the tour to learn how Stack Exchange works. Aim to have at least two complete lines. This answer is lacking in detail - you could use edit to add why this works for you, and what to watch out for. "6 words too short, read tour" – Criggie Jul 3 at 11:04
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I tend to get the pad where it should be, then tighten the fastener. If the pad rotates on the last bit of tightening and I can't hold it with my fingers, then I push the tool in the other rotation, using my fingers to push as well.

This additional force will rotate the pad without significantly loosening the fastener. Then tweak the nut tighter again.

Brake pads can be finicky wee things, and its both practise as well as technique.

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