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  1. #1
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    Reputation: bandit350's Avatar
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    hayes hfx-9 dragging

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    i have the hayes hfx-9 v7 w/bfl lever on a new kona coilair. on my rear brake the inside pad is holding constant contact w/ the rotor. i am new to hayes and only have experience w/ shim. xt hydros, so please explain in detail if necessary. all hayes gave on their website was this:

    My brake is dragging. What should I do?
    Push the caliper pistons back in their bores and center the caliper over the disc.


    any suggestions? i tried to push the pads back using a screwdriver but it didn't help. do i need to take tha pads first and then go to work? is there a specific order for removal.

  2. #2
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    i just picked up a coiler tonight and mine is exactly the same way...very annoying. you should most definatley remove the pad first and i think you use like a 9mm box end wrench to push the pistons in, but i come on here to ask this VERY EXACT question, so ill wait for a real response

  3. #3
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    I don't have practical experience on this brake. On cars, you use a c-clamp to push the caliper. The way the caliper works is it slides through the bore as the pad wears but when used, the seal just flexes enough to allow contact with the rotor and then flexes back when the fluid pressure is gone. By pushing by hand, you're likely flexing the seal when you really need to push it far enough to slide it which can more easily be done with a clamp.
    Oh sh!+ just force upgraded to cat1. Now what?
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  4. #4
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    something else

    what does the bfl lever stand for? my bike has a few 2007 components not yet posted on websites, such as the race face am stem.

    with my xt brakes i can usually loosen the wheel, wiggle it from side to side which essentially gives the rotor some room, then clamp down again. within a few pumps of the lever i am good to go.

  5. #5
    Meh.
    Reputation: XSL_WiLL's Avatar
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    BFL = Big Fat Lever

  6. #6
    Meh.
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    Quote Originally Posted by AlliKat
    I don't have practical experience on this brake. On cars, you use a c-clamp to push the caliper. The way the caliper works is it slides through the bore as the pad wears but when used, the seal just flexes enough to allow contact with the rotor and then flexes back when the fluid pressure is gone. By pushing by hand, you're likely flexing the seal when you really need to push it far enough to slide it which can more easily be done with a clamp.
    Actually most car brakes have pistons on one side and use sliding pins. The piston pushes the dynamic pad out, the entire caliper slides on the pins until the static pad hits the rotor. Then the piston retracts.

    Opposing piston brakes work essentially the same as opposing piston bike brakes.


    If it's just deflecting and rubbing a little bit, it may just need time to bed/break in.

    If you cannot push the pistons back into their bores, the system is overfilled. Remove the bleed plug at the lever, push the pistons back into their bores, this will force fluid out of the bleed port at the lever.

    If it's rubbing constantly, you need to center the caliper (or bring it back to the shop). The Nines are a post mount (radial mount in car/moto world) caliper. To center the caliper, you loosen the two bolts that attach the caliper to the adapter. Pump the lever a few times and squeeze, while holding the lever, re tighten those two bolts making sure that the caliper does not shift while you are torquing them down. Check pad clearance on each side of the rotor.

  7. #7
    Double-metric mtb man
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    Try the re-centering / piston tricks first, esp. if it is a contant drag.

    If it is intermittent, you may need to true the rotor too (instructions are in the faq at the top right of this page.
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