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So today I changed my v-brake brake shoes on my old MTB to put cartridge brake shoes.

I noticed that the order of the washers was different on both brake shoes. On the newer one the brake arm was touching both convex washers, on the older one it was touching a concave and a convex. Here's a picture:brake washer order I know that you can swap the big and small concave washers to adjust the angle of the brake arm, but is there a specific order for the concave and convex washers ?

On this Park Tool page we can see multiple different washer orders.

Does it depends on the brakes? Does it permit some fine grained adjustment? Does it matter?

  • Just being picky - you have brake pads not shoes. A brake pad might come with a separate replaceable pad in a brake pad holder. The only place that has brake shoes on a bike is in a drum brake because they're curved, and press outwards against the inside of a round drum. – Criggie Feb 5 '17 at 0:20
  • What's the technical difference between a brake pad and shoe? Curvature? – RoboKaren Feb 5 '17 at 3:32
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    I don't want to disagree with Criggie, but it seems the right hand diagram is correct if the intent is for the pad to be able to rotate. The two orange halves act as a sphere around which the pad and nut assembly can rotate. – RoboKaren Feb 5 '17 at 3:34
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    @Criggie Since I'm not English, I looked the term before-hand on Sheldon's site : sheldonbrown.com/rim-brakes.html#shoe . I agree however that shoe seems to be for the entire ensemble and not the left most part which as you indicate is called pad. As I looked on internet, there were no obvious definite answer on how to call the whole assembly, so I picked Sheldon's one. – GrecKo Feb 5 '17 at 11:11
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    would the left hand orientation permit toe in? I have never tried this, but have changed pads to be the right orientation many times thinking the left was wrong. – Paul Feb 5 '17 at 16:13
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I think it doesn't really matter. As long as you have the two curved surfaces of the orange/grey washer pairs together, then they function as one adjustable washer.

Here's what I did in testing - while the picture is rough and the angle is exaggerated, both ways of stacking the washers works fine. Theres a third way where both the grey concave washers press against the arm, and a fourth where the orange washers are both on the right side (ie a mirror of the left image here)

enter image description here

For the sake of consistency, I'd do the same thing on both sides of the wheel, but even if they were opposite I doubt you could notice a difference.


Edit: Here's the official instructions from Kool Stop about MTB brake blocks.

enter image description here

So they specify the convex washers should be by the brake arm, and the concave ones should face them, which is the right-most image in the earlier pictures.

Curiously, the order of the other washers is based on their thickness and the rim/frame/fork's requirements.

  • If you put the washers as in the left-hand drawing the angle of the shoe to the rim can't be adjusted. The orange washers in the right-hand drawing act as a kind of sphere around which the grey washers can be angled. You could not do that with the left configuration. – Carel Feb 5 '17 at 16:03
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    I've just tested - assembling canti brakes either way around on an old spare fork. It seems to make no difference to me. – Criggie Feb 5 '17 at 23:47
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Update in 2019 - I just bought some Kool Stop Eagle 2 brake pads and they look like this:

enter image description here

From left

  • Brake pad
  • Concave silver washer, thin, with flats that mate with the end of the bolt.
  • Convex black washer, also thin.
  • Gap where the V brake arm goes
  • Flat silver washer
  • 11mm nut with a cone on one side.

Documentation was not clear which way around the nut was supposed to go, but as-pictured seemed to be right, so the cone-face on the nut could sit slightly angled in the washer.

For me, this just didn't offer the range of adjustment I needed. My V brakes are behind the front fork legs, and I had to swipe a more normal pair of convex+concave washers from the previous pads.

I also did away with the nut and used the 5mm allen key/hex nut, because I didn't want to carry a weird socket as well as my normal tools.

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    Looks like those brake pads were designed to be used in very space constrained places, if you ask me. I don't have a clue, where these places might be, though - brakes should always be mounted in readily accessible places. – cmaster Apr 28 at 10:24
  • @cmaster possibly - the pads themselves have a lot of depth to wear through, which will be good. I just added this as a variation on the previous answer, because this was new to me. Probably a little cheaper to manufacture too. – Criggie Apr 28 at 13:38

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