Jiucy 7 noise solved (for me)- Mtbr.com
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  1. #1
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    Reputation: wddamf's Avatar
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    Jiucy 7 noise solved (for me)

    I have the dreaded '05 polygon rotors and my brakes howled, sqealed, and "turkey gobbled" all the time. I tried several ideas offered on this forum with minimal degrees of success. I finally solved the problem with the following procedure:
    1. I removed the stock brake pads
    2. I cleaned the rotors with denatured alcohol
    3. I grinded away the brake pad material that was contacting the rotor legs with a Dremel tool - removed about 3 mm along the lower circumference of the pads. Looking at the brakes with the bike upside down reveals how much material needs to be removed to eliminate all rotor leg contact.
    4. I then sanded the pads flat by laying them face down on a flat piece of sandpaper and carefully scrubbed them in a random pattern.
    5. Then when aligning the calipers, I lightly applied the brakes, spun the wheel, then firmly applied the brakes, then lightly tightened the caliper mounting bolts, then released the brake lever, and visually checked alignment - at this point, if the pad alignment was off, I'd nudge the caliper by hand while pumping the brake lever to help pull it into place. Once it was visually aligned, I'd clamp the lever and tighten the alignment bolts.

    This resulted in perfectly flat pads, a perfect alignment to the rotor, and absolutely no pad contact with the rotor legs - rode for 2 hours yesterday and only had a few light squeeks here and there - which I can live with.

    I learned all the ideas in the above procedure from this forum but they never solved the problem for me when applied one at a time - the above procedure worked for me.

    I've also asked my LBS to get the replacement clean sweep rotors from Avid for me as it's obvious that pad contact on ANY part of the polygon rotor legs creates noise and I don't want to have to grind on any new brake pads.

    Hope this helps!

    Dan

  2. #2
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    My solution

    I am glad to hear your problem is solved (for now). My solution was to switch to Shimano M555 rotors and carfully bevel the leading and trailing edge of the pads ( similar to high performance auto racing pads). This has worked well for me so far. I still plan on switching to the clean sweeps, but I will always bevel the pads.

    Thanks for the great post!

  3. #3
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    So is the concensus that clean sweep rotors will resolve the issue? I've noticed that the new Avid Juicy 5's and 7's come with the clean sweeps now instead of the polygonal rotors. Maybe this eliminates the turkey noise issue and is why Avid switched?
    "The stupid shall be punished."

  4. #4
    mtbr member
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    That does seem to be the consensus - however, I can report that the turkey gobble has returned on my rear brake after cleaning the bike (while just riding up and down the driveway). I'm not going to throw up the red flag until I can get the bike back on the dirt and see if the gobble fades again with a little use. BUT, the pads are now NOT contacting the rotor legs in any way, and I have the gobble just like before the modifications - so I question if pad-to-leg contact is the cause of the gobble.

  5. #5
    Meh.
    Reputation: XSL_WiLL's Avatar
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    The Polygon rotors had a few flaws. Some say it hot spots easily, others say that the rotor was stamped to uneven thicknesses, and others still will say that there is an uneven amount of exposed braking surface as the rotor spins.

  6. #6
    Nouveau Retrogrouch SuperModerator
    Reputation: shiggy's Avatar
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    Takes more than a ride or two to declare a problem solved.

    I can have brakes be silent for months, suddenly start howling during a ride and keep howling for a week or so, then go quiet again. All without me doing a thing to them.
    mtbtires.com
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  7. #7
    I like Monkeys
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    I recieved replacement clean sweeps from avid this week. During the first ride it was FINALLY without the turkey gobble but it reappeared on my rear brake on the second ride after running through some water. And it hasn't dissapeared after drying. I'm going to give everything a little time to settle in but I'm ready to try to sell these d@mned things and get some deore's or some used hope's a friend has for sale. I had some deore 525's that worked flawlesslly for 3 years. These things haven't worked acceptably for three rides.
    What do I want to be when I grow up.....Dead!

  8. #8
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    '07 Anthem here with j7's and I get that turkey gobble in the front brake. I love the analogy by the way, it hits the nail on the head! Avid send new pads but that wasn't the trick. I going to have them send a new rotor. I suspect the rotor was stamped wrong. I'll let ya know
    - 2007 Giant Anthem 0 - 24.3lbs
    - 2000 Trek 8000 LT
    - 2006 Giant OCR Limited

  9. #9
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    Did you guys go directly to Avid for the replacement rotors or did you have to go through a bike shop?

  10. #10
    Meh.
    Reputation: XSL_WiLL's Avatar
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    Quote Originally Posted by wddamf
    Did you guys go directly to Avid for the replacement rotors or did you have to go through a bike shop?
    You have to have a shop contact SRAM. SRAM doesn't deal direct with the consumer. And make sure it's a reputable shop. Some shops will tell you they called when they have not.

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