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  1. #1
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    '07 Enduro - Juicy 7 issues

    I asked this in the Brake forum, but I thought I would ask here as well since it's the Specialized forum.

    Ok, so I have a '07 Specialized Enduro with Juicy 7s...

    Constant problems with my Juicy 7s. Latest round, pads glazed after a few lengthy downhill runs and a couple of races... Removed pads, sanded, replaced, as the pads are in good order aside from the glazing. Cleaned rotors w/ rubbing alcohol, etc...

    1 race, and one ride later, same daggone vibrating sounds and pulsing sounds, feel it in the level, squeeling, etc... I have read here on MTBR and else where that the normal Juicy 7 rotors were crap. People having better luck running other brand rotors and other aftermarket pads. I have 203mm front and 180mm rear...

    What's a GOOD/GREAT rotor upgrade? Same question with Pads... Any of you guys experiencing the same thing? Any paths to resolution?

    I grow tired of constant maintenance on these brakes to keep them in decent running order...

    TIA!

  2. #2
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    Same here - I have an 07 enduro with Juicy 7's and have never been happy with the performance. Have you tried the organic pads? In my experience they vibrate and squeal much less. They seem to have less power and wear out faster though. What I have tried recently is going 50/50 with organic and metal pads and so far that seems to be working pretty good - quiet and pretty good power. Overall I find the 7's to be disappointing. I have ridden and enduro with Hope V2's and those are far superior in both power and feel... I will be upgrading as soon as I can afford.

  3. #3
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    I have the same brakes on my '07 Stumpy and I´m happy with them. The only problems that I have had with them are that at the begining they were very noisy and sometimes the rotor rubbs with the pads.

    Now I´ve changed the rear pad for an organic one and at the begining I didn´t like too much how it goes, too much noisy, but now it goes well. Also, I didnt like the feeling of the brakes with the organic pad at the begining.

  4. #4
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    Quote Originally Posted by Jeepnut22
    What's a GOOD/GREAT rotor upgrade? Same question with Pads... Any of you guys experiencing the same thing? Any paths to resolution?
    I had that problem for about the first year with my Juicy 7's before I switched to straight organics. I tried several, but my favorite are the cheap a** Aztec ones from Performance. They're only like $15 a pair, and have great stopping power, and are completely silent. I weigh about 220 with gear, so if they can stop me quietly, chances are they'll work for most people.

    My brakes haven't made a peep in over a year.

  5. #5
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    Switch to organic pads. They have more power, make less noise, but don't last as well as the sintered. I like the juicies well enough and don't feel the need to change. But I am sure other newer designs are better.

  6. #6
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    Quote Originally Posted by MTBJong
    Switch to organic pads. They have more power, make less noise, but don't last as well as the sintered.
    Organics generally have less overall power, but modulate better and are more quiet. Try adjusting the calipers. If you are getting vibrating and rubbing noises then your calipers probably aren't lined up well. this will wear your pads at an angle and just make things worse.

  7. #7
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    With the Avids, they have the Convex/Concave washers on each of the mounting points. I have adjusted that way, as well as the LBS has adjusted them. Things still seem to quickly degrade.

    Thinking about Galfer disks and some brand of organic pads. We'll see...

  8. #8
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    The vibration-pulsation is either from 1) a warped or defective rotor or 2) a sticky piston, which will manifest itself into a dreaded turkey warble sound. The rear brake is more prone to sticky pistons because a lot more dirt gets kicked into the caliper than in the front.

    First check the problem brake for a warped rotor and straighten it out following the instructions on the Brake FAQ forum.

    If the rotor is not visibly warped, remove the wheel and pull the pads out of the caliper. While looking at both pistons squeeze the brake lever two times very slowly to determine which piston is sticking. Warning—do not squeeze the lever more then two times because you will not be able to fit an open end wrench in-between both pistons to push then back into their bores. Clean all of the grime off of the caliper and pistons (I use a Q-tip dipped in a little rubbing alcohol). Push the good piston back into its bore by inserting an open end wrench between the two pistons and applying a steady uniform force to the end of the piston directly back into its bore. Do not apply a wedging type angular force or you may wedge the piston in its seal. Also make sure the bike is upright (no up side down) when you push the piston back otherwise you will need to bleed the brake. Note; the open end wrench will need to be large enough to cover the outside diameter of the piston. With the caliper and pistons cleaned up, dribble a small amount of DOT brake fluid around the outer diameter of the sticky piston—remove the caliper and turn it on its side and let gravity do its work. Remember to clean all of the DOT fluid off of any painted surface immediately with soap and water.

    Try squeezing the lever again after you let the brake fluid penetrate the seal for about five minutes. If this method does not un-seize the piston hold the good piston back with your open end wrench and slowly squeeze the lever until the bad piston starts to come out about two lever strokes. Clean any dirt off the piston with a Q-tip and coat the sides of the exposed piston with DOT fluid and a clean Q-Tip. Push the piston back in and squeeze the lever. Both pistons should extend equally with each lever squeeze. Repeat this process a few more time if necessary. You may need to bleed the brake after this process. Recheck the piston again after a few rides. If you can not free up the sticky piston, then the caliper will need to be rebuilt with new pistons, seals and o-rings, which will run you about $50.00 for a kit.

    As for your glazing problem cindered pads will be your best bet even though they are the noisiest. Larger rotors also run a litter cooler if your front and back rotors on your bike are not maxed out at 203mm and 185mm respectively.

  9. #9
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    Thanks for the info bwalton!!

    I'll check the rotors and pistons before buying anything.

  10. #10
    DSG
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    I have the turkey warble on my front brake since I changed the pads. It only happens at a very slow 'chillin' speed at which point I can feel it through the handlebars.

  11. #11
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    DSG, normally when you install new pads you need to push the pistons all the way back into their bores in order for the new pads to fit over the rotor and to reset the pads to rotor clearance. Set the pad clearance by squeezing the brake lever 10 times after you push the pistons back and roughly center the caliper around the rotor--also you must realign the caliper as well with the CPS hardware. One problem that I have encountered with Avid Juicy caliper’s is that the pistons get wedge or cockeyed in their seals if you do not push them straight back into their bores (see my post above). This will cause one piston to lock up or bind against its seal. The other (opposing) piston with less drag will move out when you squeeze the lever and push one pad against the rotor. Since the other pad under the stuck piston does not move the rotor deflects into the pad (like a mechanical disc brake does) and the diagonal slots, which are now slightly bowed, resonate against the stationary pad and vibrate. If the gap was between the locked pad and the rotor was smaller like the gap on a mechanical disc brake then the vibration would be barely noticeable. The sticky pad also forces the good piston to push beyond its stroke thereby exasperating the vibration because the pressure it exerts falls of sharply at the end of its stroke and so does your stopping power as well. The other problem that a sticky piston creates is that it is virtually imposable to align the caliper properly.

    My 07 J5 violently vibrated the rear end of my 07 SJ FSR after the pads went through their initial break in period (embedded into the rotor). I tried everything, different rotors, which changed the frequency of the vibration, organic pads, sanding and cleaning the rotors and pads, countless caliper alignments, new G2 rotors and bleeds—all of these procedures failed to fix the problem. Then I read the fine print on the first page of Avid’s Juicy service manual, which talked about stick pistons and discovered that my inside piston was sticking. After I rebuilt the caliper the vibration and lack of power problem were fixed.

    Unfortunately, all bicycle hydraulic disc brakes suffer from sticky pistons and warped rotors so learning how to maintain (i.e. keeping your pistons cleaned and lubricated) your disc brake(s) is critical to their performance. They are not maintenance free especially if you ride on dusty or muddy roads.

  12. #12
    DSG
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    Thanks for the detailed response. That looks like a job for a sunday afternoon

    It does see a bit of mud, it spends most of its time looking like this:



    Quote Originally Posted by bwalton
    DSG, normally when you install new pads you need to push the pistons all the way back into their bores in order for the new pads to fit over the rotor and to reset the pads to rotor clearance. Set the pad clearance by squeezing the brake lever 10 times after you push the pistons back and roughly center the caliper around the rotor--also you must realign the caliper as well with the CPS hardware. One problem that I have encountered with Avid Juicy caliper’s is that the pistons get wedge or cockeyed in their seals if you do not push them straight back into their bores (see my post above). This will cause one piston to lock up or bind against its seal. The other (opposing) piston with less drag will move out when you squeeze the lever and push one pad against the rotor. Since the other pad under the stuck piston does not move the rotor deflects into the pad (like a mechanical disc brake does) and the diagonal slots, which are now slightly bowed, resonate against the stationary pad and vibrate. If the gap was between the locked pad and the rotor was smaller like the gap on a mechanical disc brake then the vibration would be barely noticeable. The sticky pad also forces the good piston to push beyond its stroke thereby exasperating the vibration because the pressure it exerts falls of sharply at the end of its stroke and so does your stopping power as well. The other problem that a sticky piston creates is that it is virtually imposable to align the caliper properly.

    My 07 J5 violently vibrated the rear end of my 07 SJ FSR after the pads went through their initial break in period (embedded into the rotor). I tried everything, different rotors, which changed the frequency of the vibration, organic pads, sanding and cleaning the rotors and pads, countless caliper alignments, new G2 rotors and bleeds—all of these procedures failed to fix the problem. Then I read the fine print on the first page of Avid’s Juicy service manual, which talked about stick pistons and discovered that my inside piston was sticking. After I rebuilt the caliper the vibration and lack of power problem were fixed.

    Unfortunately, all bicycle hydraulic disc brakes suffer from sticky pistons and warped rotors so learning how to maintain (i.e. keeping your pistons cleaned and lubricated) your disc brake(s) is critical to their performance. They are not maintenance free especially if you ride on dusty or muddy roads.

  13. #13
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    My Juicy 7s came with my Enduro...

    I'll have to check online for maintenance instructions.

  14. #14
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    Quote Originally Posted by Jeepnut22
    I asked this in the Brake forum, but I thought I would ask here as well since it's the Specialized forum.

    Ok, so I have a '07 Specialized Enduro with Juicy 7s...

    Constant problems with my Juicy 7s. Latest round, pads glazed after a few lengthy downhill runs and a couple of races... Removed pads, sanded, replaced, as the pads are in good order aside from the glazing. Cleaned rotors w/ rubbing alcohol, etc...

    1 race, and one ride later, same daggone vibrating sounds and pulsing sounds, feel it in the level, squeeling, etc... I have read here on MTBR and else where that the normal Juicy 7 rotors were crap. People having better luck running other brand rotors and other aftermarket pads. I have 203mm front and 180mm rear...

    What's a GOOD/GREAT rotor upgrade? Same question with Pads... Any of you guys experiencing the same thing? Any paths to resolution?

    I grow tired of constant maintenance on these brakes to keep them in decent running order...

    TIA!

    Dude...I tried everything thing that has been mentioned on this site. Save your time & money and buy some decent brakes. I had Juicy 7's that howled. Read the reviews about the Elixirs, tried them....still howled. Even had the "new" G3 rotors. So what did I do? I bought Galfer rotors and Swiss Stop brake pads. Guess what? They still howled...can you believe it? SRAM was of no help and I parted ways with the Avid/ SRAM forever. Boxed them up sold them on Craigslist and I'm now running Magura Marta SL......they are far better than anything SRAM/ Avid could produce. The modulate better, better power...one finger braking and above all else...whisper quiet, even when wet.

    Save your sanity & wallet from the torture that is SRAM/ Avid

  15. #15
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    Interesting Cmoorejr... I have heard the same from others. Also have heard people having little to no issues. I have thought about going the Hope M4 route, but want to try and get these working the way I want/expect.

    I will definitely be cautious in how much money and time I spend on these before giving up on them. Thanks for the input as well...

  16. #16
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    Quote Originally Posted by Jeepnut22
    Interesting Cmoorejr... I have heard the same from others. Also have heard people having little to no issues. I have thought about going the Hope M4 route, but want to try and get these working the way I want/expect.

    I will definitely be cautious in how much money and time I spend on these before giving up on them. Thanks for the input as well...

    No problem Jeepnut. Good Luck!

  17. #17
    DSG
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    Right. Remove the pads and pushed the pistons back in. Put it back together again. The first press of the lever causes both pistons to get stuck so the wheel barely turns.

    Looks like they need bleeding and servicing I guess.

  18. #18
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    I won't be of much help because I've had pretty good experience with (2) bikes that have Juicys on 'em. The only time they've ever howled is sometimes in wet/moist conditions. Other than that, they've been quiet.

    I am using Alligator rotors on one bike, and have replaced both brakes' pads with EBC units on occasion.

  19. #19
    DSG
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    Fixed my juicys over the weekend. The reason for not being able to push in the pistons is because the red adjuster on the lever needed to be wound fully back. That allowed the pistons to be pushed fully back in. A little bit of aligning the caliper with the rotor then cured all squeeling!

  20. #20
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    It's not the rotors, it's the brake pads and the crappy design. I had Juicy 7's on both my Niner and my Yeti. I sold the Niner and my new hardtail came with Juicy brakes as well. I was so tired of the Turkey Gobble on my past bikes that I took them off the bike while it was being built up and replaced them with Shimano XT brakes. I kept the Avid rotors though, and the brakes work like a dream. They are rock solid and nary a squeal or gobble to be heard. I will never buy Avid brakes again.

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