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I have dual pivot brakes on my Shimano 105 road bike. The wheels are Shimano RS010's.

For some reason, the right pad on the rear brake is too high vertically, it's basically hitting the tire, but it's in the lowest possible position, and I don't know how to move it lower. In contrast, the left pad has plenty of vertical distance from the tire. Simply rotating the brake calipers around the central pivot will not work because the pads will no longer be centered and equidistant from the wheel.

photo of brake pad hitting tire

What adjustment needs to be made here to correct this?

2 Answers 2

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There is a small grub screw on top of the brake, near/above the long pivot, that is supposed to be used for centring. It also changes the brake geometry. This adjustment requires a 2 or 2.5mm allen; it should usually be flush with the brake and should certainly not protrude as much as yours does!

Often they work their way out or are maladjusted so check this first. You may wish to put a drop of blue loctite on the thread to prevent it moving unintentionally again, but now you know where the adjustment is, you will know when you need to use it again.

It also has an effect (a small one) on the brake power and cable pull ratio, so it's quite fun to experiment with.

Also check the wheel is in the dropouts fully and no quick-release springs are the wrong way round.

Photo shows grub screw is adjusted too far out and should be wound in until flush with brake to see if that solves problem: enter image description here

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  • Are you referring to the screw end jutting out the top? There seems to be no access to the screw head, so I don't know how to adjust that. I've just added some more photos to that album, including photos of the dropouts. The right dropout screw is slightly bent. Should this be a concern? I don't know how I'd even replace it, it's not removable as-is, would need to be sawed off or something.
    – Jugdizh
    May 22, 2022 at 18:18
  • The bent dropout screw looks okay - it is a stop for when you put the wheel in, so that the axle always ends up in the same place. You could remove it completely but then its fiddlier to get the wheel parallel. If it bothers you, either try and straighten it and if it snaps, just replace the bolt.
    – Criggie
    May 22, 2022 at 18:50
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    Thank you! Adjusting the grub screw did the trick, and my brakes are now well aligned. The grub screw took a tiny hex wrench, same size as the screws on the brake shoes.
    – Jugdizh
    May 22, 2022 at 19:39
  • @Jugdizh glad to be of assistance!
    – Noise
    May 22, 2022 at 21:01
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you can buy longer drop brakes,37mm to 47 mm are short drop brakes mainly on most newer bikes,then you have 47mm to 57mm for some older retro steel bikes,you can also get even longer drop dual pivot brakes to fit much older bikes,brakes fitted need to have some adjustments left either way for different rim combos

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    This is true, and it would have been my first thought. But it would be very strange for a bike to come stock with the wrong type of brake. And the accepted answer said that the brake was probably uncentered.
    – Weiwen Ng
    Dec 17, 2023 at 10:49

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