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  1. #1
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    Avid Juicy Ultimate 7 howl/vibration on Stump FSR?

    Just bought a new 08 Stumpjumper FSR Elite with the Juicy Ultimates and on the 2nd or 3rd ride developed a loud squeal and vibration on the rear brake. I see from the other threads that some of the Avids have this problem. I have used Hayes 9 and never had this problem. I cleaned the rotor and pads, it's centered and not bent. Anyone else have this really annoying problem?

  2. #2
    Ahhh the pain....
    Reputation: Raybum's Avatar
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    Yep, I have the exact same bike...and funny noises. The noises will change throughout a ride it seems whether the brakes are heated up or not. Today they even seemed to do a sort of slip-stick-slip-stick thing that sent shudders through the bike (and me). These are new pads (2nd set).
    I'm living with it for now, but next time I take it in for a free tune-up, I'm going to have them look at it...

    Ray

  3. #3
    TNC
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    noMAD man
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    This problem is/has been discussed at much length. There is a megapost here right now that is bigger than the Webster's Dictionary. Look for the "Turkey Gobble" thread. Many others not too far down the page also cover it. There is also one on the Specialized forum going on right now covering the same bike you have. Don't take this as a flame, but I don't want you to miss out on the discussions and possible solutions that are covered in many current posts up to this point. I solved mine.

  4. #4
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    Thanks. I have read a bunch of posts but somehow missed the megathread. So what was your remedy?

  5. #5
    One Gear
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    Try organic pads first.

  6. #6
    TNC
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    After trying many of the listed suggestions and many I'd run across from working at a shop, changing pad composition and backing material is what worked for me. As .40AET suggested with organic pads, I think that seems to be one of the best and easiest solutions. I went with Jagwire semi-metalic pads with alloy backs. Something in the material composition of the OEM Avid pads seems to allow this to occur in certain situations.

    In reality there may be something else going on to cause the turkey-gobble-vibration, but the pads seem to be the primary cause that yields this symptom in the final analysis. I even suspect that some riders and their bikes might have different issues across the spectrum of brake mounting, tab orientation, rotor condition, etc, etc., but the Avid pad design may be the final element that brings on the noise/vibration in Juicy's and Elixir's. The application of a different pad and backing material seems to have a damping effect that the OEM sintered pads don't have.

    I have 2 sets of Elixirs...4 separate caliper units...and 1 of those units produced the same symptom on 3 bikes, so my problem was probably not a mounting or tab issue. Even a new set of OEM Avid sintered semi-metallic pads didn't fix the problem. Installed the Jagwire pads and poof!...noise, vibration gone ever since. I also have a set of Juicy 5's on an SJ FSR. The rear unit had the noise/vibration. Jagwire pads installed and poof!...gone. Can I explain the exacting, engineering element that is being addressed by the application of a different pad and backing material?...not really...but it seems to be some kind of weird harmonic deal that can't be damped or absorbed by the OEM pads. At least this is my best assessment.

  7. #7
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    i agree
    try organic pads or some softer non-metallic pads. it is really weird how the pad material will make a difference!

    my bike has avids, low end ones, and after about 20 rides, the rear brake started howling and i got this grinding sound like thepads were gone, especially after they heat up after a long descent. i inspected them and they were about 2/3 worn, plenty of material. but they had the semi-metallic pads. so i replaced them and the noise is gone.

    zaskar1

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