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Brake noise/moaning

Discussion in 'The Shop' started by DirtyMartini, Dec 15, 2010.

  1. DirtyMartini

    DirtyMartini Chimp

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    I used to have a 180mm shimano XT rear rotor and I just went up to a 203mm shimano XT rear rotor. Brake caliper is Shimano SLX.

    The 180mm was nice and quiet. The 203mm moans when braking. It sounds like rotors sound when they get wet. The wheel spins freely when not braking, there' no rubbing, the caliper looks aligned, the brake pads are fairly new.

    Any suggestions?
     

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  2. infamous24

    infamous24 Chimp

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    Clean the rotors with rubbing alcohol and maybe try lightly sanding the face of the pads.

    It could also be that the pads just need some time to adjust to the new rotors. They might not be exactly parallel to the rotor right now, but after some use they should be.
     
  3. skurfer333

    skurfer333 Monkey

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    ^^exactly. If the 203 rotor is brand new, then you'll have to brake it in. After the sandpaper/rubbing alcohol, find a big hill and make a few trips down it with the brakes on.
     
  4. IH8Rice

    IH8Rice I'm Mr. Negative! I Fail!

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    thats not really how you are suppose to break in pads..
     
  5. skurfer333

    skurfer333 Monkey

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    Why not? Works like a champ.
     
  6. mattmatt86

    mattmatt86 Turbo Monkey

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    I usually break in pads/rotors by riding around the parking lot holding the brakes, It's a workout too.
     
  7. IH8Rice

    IH8Rice I'm Mr. Negative! I Fail!

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    to glaze over your pads
     
  8. DirtyMike

    DirtyMike Turbo Fluffer

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    Sooooooo....... Check this..... Its all about surface RA... that translates to how rough the surface is.

    Glazing is something that happens, its normal.... as to how much... thats another story. Issue here is the Surface RA on the rotor is nice and hi, yet the pad is nice and low.

    makes for a wonderfull noise. Fun aprt now is when you put the other rotor back on, its gonna make noise now too since the new rotor is starting to Deglaze the old pads ETc Etc.



    What you need to do is..... Hone the two together.

    Stay with me here guys........ Really fast way to "burn" the pads and rotors together, and make them last longer..... No this isnt bull****..... no this isnt a joke..........

    Take a paper towel, put some wd40 on it, and lightly wipe down the rotors surface. Then ride a moderate hill, steady grade....... ride the brakes a bit untill you burn off the wd40........... WD40 is a great honing agent, eliminates noise, gives you the longest pad life, best stopping power.

    Dont knock it till you try it
     
  9. skurfer333

    skurfer333 Monkey

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    I immediately start sweating and biting my nails at the idea of WD-40 anywhere near a bike
     
  10. IH8Rice

    IH8Rice I'm Mr. Negative! I Fail!

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    wd40? no thanks
     
  11. infamous24

    infamous24 Chimp

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    That's a terrible idea. WD40 has oil in it, which obviously doesn't mix well with braking surfaces.
     
  12. IH8Rice

    IH8Rice I'm Mr. Negative! I Fail!

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    itll make you learn to not use your brakes though
     
  13. slimshady

    slimshady ¡Mira, una ardilla!

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    Riding brakeless FTW!