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  1. #1
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    Brand New Bike w/Brake Noise?

    I recenly purchased an '07 Giant Anthem 2 with the Avid Juicy 3 brakes. On my first trail ride I noticed an odd harmonic/screeching noise coming from the rear of the bike. It is periodic and to me sounded like the pad was dragging on a high spot on the rotor. This noise went away when I applied the rear brake slightly.

    Took the bike back to the shop and they fiddled with the rear brake. He said something about the rotor not being true (I really wasn't listening too well...I was in a rush to get back to work). I was able to take it for a quick test ride before I loaded it up on the rack and headed back to work...the previous issue seemed to have gone away.

    Later on tonight I go out for a neighborhood ride with my wife and sure as **** the damn noise is back again. Same exact noise as before and it goes away when I slightly apply/ride the rear brake.

    Sounds to me like the caliper/pad is still rubbing on the rear rotor. I visually inspected the rear rotor as the wheel spins and it the rotor looks to be true. So now what? I hate to have to keep bringing it back to the friggin shop, but this noise is horrid out on the trail (not to mention embarrasing that I've spent this much money on a bike and it sounds like I'm sporting a 20-year old Huffy that I just pulled out of a lake).

    I know noise Avid brakes seems to be a hot topic. I searched and appear to have only found people with the noise issue while they are applying the brakes. Couldn't find anything regarding noise when the brakes aren't clamping down on the rotor.

    I greatly appreciate any help you can throw my way.

  2. #2
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    Neglected to include one aspect of the issue. This sound only occurs while my weight is on the bike. I cannot replicate the sound if I lift the rear off the ground and free spin the rear wheel.

  3. #3
    Meh.
    Reputation: XSL_WiLL's Avatar
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    Ride it some more, make sure that it's all broken/bedded in.

    If you get noise while you aren't braking at all, it means that your frame is flexing or the wheel is shifting in the dropout. This is allowing the pad to just barely touch the rotor.

  4. #4
    komojo dragon
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    I have this exact scenario, new bike today, fine at shop riding around just started to bed the brakes in a bit. Loaded it in car and took it home. 1st ride, started with a long downhill commute to trail, and squeaking at first thought it was the front, then finally applied the rear brake, and the noise stopped, for a moment then started again, more load = louder noise... avid 7's 160 rotors. on the transport home the bike was laying on side rotor side down on an old foam mattress pad. virtually no squeal with bike lifted and freelly rotating wheel, or with brake applied.

  5. #5
    Meh.
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    Flex is the likely culprit. Recenter the caliper with your weight on the bike.

  6. #6
    komojo dragon
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    xsl, would this be flex of a new wheel which affects the angle of the rotor within the caliper? why would the noise stop for a moment after brake application?

  7. #7
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    I tried the trick where you loosen the caliper bolts, pump the brake 6-7 times and retighten while you hold it down. This made the issue significantly better, however I am still getting a small amount of the noise when the bike is tilted with my weight on it (i.e. taking a sweeping turn). The shop suggested the hub may need to be torqued down a bit more. They also advised this is somewhat normal during the break in and that everything is retorqued down to spec when I bring it back in for my tuneup after the break-in. I hate being "that guy" who has to take the bike back for every little thing...but unfortunately I'm relatively new to bike mechanics so I'm at the mercy of the shop until I can get myself up to speed on adjustments and repairs.

  8. #8
    komojo dragon
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    It sounds like you might be on to something with the hub internals allowing some flexion/wiggle room for the axle/ rotor?... When I look down at just the rotor spinning it doesn't seem to be off..
    My shop for the same problem as a stop gap measure ,they are 70 miles away , said to try loosening the skewer then look into the caliper and see if you can get the tiniest amount of space between the pads and rotor inside and out. When I looked at that gap prior to trying this, the rotor was difinitely contacting the top of the inside brake pad in the caliper! In my case then just dropping the axle a bit just on the rotor side allowed the rotor to sit more evenly in the caliper. I had to do this a few time before the noise subsided quite a bit - then went for a ride. The noise was down to an occaisional crickets worth for the first half to two thirds, then going up and down some bumpy singletrack the noise was back on the return home , but at least I got to actually enjoy the bike for awhile without the distraction of major noise! lol

    I am going to try the adjustment you made as well, and see what that does! I did notice that when i apply the rear brake the rear offending rotor deflected in at the back of the caliper, and outward at the front of the caliper - so there is some funky thing generally happening here.

    Good luck with yours, and let me/us know what happens when the hub is retorqued!

  9. #9
    shred my gnar
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    xsl... bear with me... so if the rub (wounded humpback whale sound) only occurs while cranking through a turn or in rocks while torquing on the bars then it is most likely flex, of some kind (wheel or frame), that is causing the rub... right?

    so... on my current set-up (new chumba xcl... been on about 6-7 rides of varying length, juicy 7s w/185mm rotors) the front rubs whether im on in or not... to the point while climbing that i seem to be able to feel the resistance... i can definately feel the rub in my bars. i have reset the cps bolts a couple times (without body weight on the bike) and it seems to help for a little while but it eventually comes back... not immediately but by the end of the same ride or by the next ride.

    i figured the pads and rotors were broken in by now... i really have no idea what that time frame is.

    so... if reseting the cps bolts doesnt fix the issue for more than a half ride what is the next step??? thanks... the last thing my ass needs is additional resistance on the climbs!

  10. #10
    Meh.
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    I only caught about half of what you said... But... Are you resetting the CPS and centering correctly? Loosen just enough that the caliper can wiggle, pump brake levers, squeeze and hold, alternately tighten bolts (making sure caliper does not shift). Make sure there is room on both sides of the rotors, if there is not, do it again. Use the business card trick if you have to.

    Make sure your hub has no play and all that. Make sure your QR is tight.

    If all else fails, check the pistons. Make sure they are extending and retracting properly.

  11. #11
    Shortcutting Hikabiker
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    Quote Originally Posted by happy_ending
    so... if reseting the cps bolts doesnt fix the issue for more than a half ride what is the next step??? thanks... the last thing my ass needs is additional resistance on the climbs!
    Is your rotor true?

    A few things could cause rubbing that occurs with the bike weighted or not.

    This is in order of most likelyness.

    1. Rotor is bent
    2. Caliper is not aligned
    3. Wheel not all the way in dropouts or in crooked.
    4. Brake lever has been squeezed w/ wheel out
    5. Hub loose

    If the rubbing only occurs when riding it is something due to flex in the frame/wheel. Make sure your QRs are tight! Adjust the brakes with the QRs tight (especailly on the front), if you adjust the brakes with it loose then tighten it up it wont be the same. Check the hub for play. Check suspension bearing/bushings for play.

  12. #12
    komojo dragon
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    My caliper seemed to be out of alignment with the rotor... I reset the axle up into the dropouts both sides ( my first try at fixing the issue was dropping the axle to try to get the rotor more centered in the caliper - didn't work for that long ) and did the loosen capliper, apply brakes - retighten carefully. I repeated this step several times ( i think the pistons had gotten a little uneven in the caliper.. ) until when I applied the brakes I could detect just a tiny hint of deflection of the rotor only at the back of the caliper vs quite a bit of deflection front and back. Wheel now turns freely, rotor seems equally spaced within the caliper, and a brief ride around lot = so far no noise. Will try a longer ride this weekend... Thanks for the advice!

  13. #13
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    I've got the same problem

    A1, I've got the same problem exactly as you've described it. I'm using Juicy 7's on a Motolite. When I took it to my LBS, the mechanic, without any prompting from me, suggested the problem was play in my hub bearings. (My wheels are new, FSA XC-300.) He then grabbed the tire with one hand at the top and the other at the bottom and applied some lateral stress to show me the rotor moving over and touching the caliper. I am still unconvinced. I do believe there is some flex somewhere but don't know for sure that it is the hubs, the frame, or a combination of both.
    Anyway, I was able to fix the problem in front by going with a smaller rotor - from 185mm to 160 so now the rotor deflection is not so great. I continue to have the problem in the rear though (already a 160mm rotor). I can't 'torque' down the hub bearing because they are the cartridge type - they can't be adjusted. I might even consider new wheels if I KNEW that was the problem but I don't.
    What type of wheels are you using and what size rotor are you using in the rear? I will watch your post with interest as I too desire a quiet ride. I think you are getting some good tips here so hang in. By the way, I think the reason there is so much chatter about Avid noise issues is because so many people use Avid breaks, not because they are inferior in any way. Good luck.

  14. #14
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    ...

    Quote Originally Posted by happy_ending
    xsl... bear with me... so if the rub (wounded humpback whale sound) only occurs while cranking through a turn or in rocks while torquing on the bars then it is most likely flex, of some kind (wheel or frame), that is causing the rub... right?

    so... on my current set-up (new chumba xcl... been on about 6-7 rides of varying length, juicy 7s w/185mm rotors) the front rubs whether im on in or not... to the point while climbing that i seem to be able to feel the resistance... i can definately feel the rub in my bars. i have reset the cps bolts a couple times (without body weight on the bike) and it seems to help for a little while but it eventually comes back... not immediately but by the end of the same ride or by the next ride.

    i figured the pads and rotors were broken in by now... i really have no idea what that time frame is.

    so... if reseting the cps bolts doesnt fix the issue for more than a half ride what is the next step??? thanks... the last thing my ass needs is additional resistance on the climbs!
    Happy Ending,

    Sorry to hear about your issue. Can I ask what procedure your using to adjust the caliper bolts?

    First thing I would do, is put the bike on a stand and spin the front wheel, eyeing which side of the rotor is rubbing. Sometimes it helps to use a white piece of paper behind the rotor to get a better visual of the rotor's position via the brake pads. Once you've determined which side is rubbing, loosen the caliper bolts and adjust the caliper position until there is no rub at all. Retighten the bolts.

    Also, check to see if your rotor has not been bent at this time. The Juicy 7s should be fairly easy to align. Let me know how it goes!

    A.
    Simple | Proven | Reliable

    http://chumbaracing.blogspot.com/

  15. #15
    komojo dragon
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    wheels : mavic crossrides also rear noise problem. after above procedure - first part of 1 hour xc type ride with wife, none to very little noise, return home the cricket noise returned, and my wife said that's pretty annoying - still not right... seems to return after riding for 45 minutes or so....

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