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The rear brake of my road bike closes unsymmetrically which results in bad braking performance and the rear wheel is getting pushed to the side. The Video describes the problem best.

The arms of the brake move and close symmetrically if I uninstall the brake an push the arms with my hand together.

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  • If the front brake does not have the same symptom then brake them down and see what is different.
    – paparazzo
    Feb 28 '16 at 19:20
  • Based on the still, its a single pivot caliper brake? So if one side moves differently to the other its generally a spring with variable springiness on each side. You can look for small plastic blocks used to pre-tension the spring and see if the slow side can be adjusted, or strip the caliper down and clean it totally then reassemble.
    – Criggie
    Feb 28 '16 at 22:58
  • @Frisbee the front is dual pivot, you don't need to disassemble it to see the difference.
    – ojs
    Feb 29 '16 at 18:15
  • @ojs Well I don't see a rear brake. How can you assume the rear and front are different? If they are different then clearly would not need to disassemble. Even "break them down" does not necessarily mean disassemble to me. If they and the same and behave differently then what is different.
    – paparazzo
    Feb 29 '16 at 18:29
  • @Frisbee look at the left in the still image, there's a rear derailleur visible. These are 2000s Campagnolo brakes that have single pivot in the rear for saving weight and dual pivot in the front.
    – ojs
    Feb 29 '16 at 18:33
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In the very last image of the video there appears to be a small screw hole in the caliper. Looking from the right side of the bike it is behind the exposed cable, between the adjuster and the cable clamp. That screw will adjust the spring tension. Turning the screw "in" will increase the tension on the spring. The increased tension will delay the brake movement relative to the other side. Based on your video I would think you need to back the screw out. Start with 1/4 turns. As others have commented if you can't adjust the issue away it may be time to strip them down and clean and lubricate the pivot points.

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  • Just turning the screw and cleaning didn't solved the issue. But I think it was a part of the solution.
    – Penta
    Mar 1 '16 at 22:41
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I am not sure what exactly solved this issue. But to get the brake working properly I cleaned the brake, put WD40 on the pivots, changed the cable with an 1cm longer one, changed the alignment of the brake, strengthened the bolt to the frame and now it works better.

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    Don't use WD40 or CRC - they're water removal agents, not lubricants. In the future, use anything else. Light machine oil, lithium grease, copperslip, anything beats WD40 for oiling.
    – Criggie
    Mar 2 '16 at 0:10

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