Odd Disc Brake Sound

bradsbeard
bradsbeard Posts: 210
edited August 2015 in Workshop
Have Shimano BR-785R on my Giant Defy.

Have a constant 'click' sound which is only when the bike is in motion from the front. It like something is flapping. If I spin the wheel there is nothing.

Any ideas what or where I should be looking as I can't see any rubbing with rotor.

Comments

  • Bearings? Putting weight on them is making them click?

    You could also take the pads out of the front caliper and then go for a short, slow ride. That will tell you if its the disc hitting the pads or not.
  • bradsbeard
    bradsbeard Posts: 210
    Have to say 1st ride sound wasn't there. Took the front wheel out and next ride this sound was there.

    Went over with fine tooth comb today and cannot see where it is coming from.
  • Front derailleur cable or the cage itself hitting on the crank as it passes.
  • bradsbeard
    bradsbeard Posts: 210
    Di2 so no cable and defo not the cage.

    I played about with tension of the QR and seemed to have cured most of it. Wasn't any where near as prominent on todayss ride as previous rides but did start under heavy braking. I can just see the pads don't hit the disc simultaneously one side (fork) hits before the other.
  • kajjal
    kajjal Posts: 3,380
    Sometimes with disc brakes the action can be a little uneven. To resolve this adjust by eye until you have enough gap either side but both pads hit the disc at the same time. If you really over tighten the QR after setting the brakes up it can make the disc rub or make wheel spin less smoothly and affect braking.

    Once setup give the brakes a good test down a hill stopping a few times to make sure all is OK.
  • rafletcher
    rafletcher Posts: 1,235
    Sometimes with disc brakes the action can be a little uneven. To resolve this adjust by eye until you have enough gap either side but both pads hit the disc at the same time.

    These are hydraulic brakes so you can't individually adjust the pad position.

    Sometimes on new bikes the caliper might not be absolutely accurately centred over the disc. Loosen the bolts holding the caliper to the fork, clamp on the front brake, then re-tighten the mounting bolts. That should centre it, and allow the pads to retract symmetrically. But sometimes when removing / replacing wheels the set-up might not be absolutely the same as when you started, but hey, that's life :D
  • hobbo31
    hobbo31 Posts: 107
    Had the same problem found it was the caliper that was not 100% parallel to the disc, just reset and try again
    Giant Trance X1 2008
    Gary Fisher Cobia 29er 2010
    Ribble Road Bike
    Giant XTC Composite 29er 2012
    Giant Defy Advanced Pro 0 2015
  • kajjal
    kajjal Posts: 3,380
    Sometimes with disc brakes the action can be a little uneven. To resolve this adjust by eye until you have enough gap either side but both pads hit the disc at the same time.

    These are hydraulic brakes so you can't individually adjust the pad position.

    Sometimes on new bikes the caliper might not be absolutely accurately centred over the disc. Loosen the bolts holding the caliper to the fork, clamp on the front brake, then re-tighten the mounting bolts. That should centre it, and allow the pads to retract symmetrically. But sometimes when removing / replacing wheels the set-up might not be absolutely the same as when you started, but hey, that's life :D

    I was referring to the caliper, often the hold on the brake method does not provide the best result. If you do it by eye you can see if the brake action is uneven and get the best result.