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  1. #1
    Dudette
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    New question here. BB7 weird experience

    Hi all, I had a weird experience with my Avid BB7's yesterday and was hoping for some insight. I had hopped my bike while riding down a level stretch of road. When I went to apply my front brake after landing, I was only able to depress my level minimally and it felt like the pads had locked up on the rotor itself. After trying to depress the lever a couple of times rapidly after that, something felt like it "gave" and the brakes began working normally again. This happened to me one time last week as well, but I didn't think too much of it at the time. But looking back, it happened when I went over a waterbar and landed my bike back down on the trail. Anyone else ever experienced this or have any idea what could be wrong? I checked my cable at both the caliper and lever ends and everything appears fine.

  2. #2
    Short-Change-Hero
    Reputation: gregnash's Avatar
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    check your cable lines. Sounds to me like the cable is catching on something somewhere and the "give" is it finally releasing.

  3. #3
    g3h6o3
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    Yes, exactly, check the lines. My guess is that your housing sticks on the cable and then it can catch on the barrel adjuster and get stuck there.
    Check out my SportTracks plugins for some training aid software.

  4. #4
    Dudette
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    Could adding some lube to the cable fix this?

  5. #5
    g3h6o3
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    It can help but in my experience it doesn't last long, if it helps. When this happens to me it's usually because the cables have "swollen" so no grease or lube can help much. How old are the cables & housing?
    Check out my SportTracks plugins for some training aid software.

  6. #6
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    Sounds like the cable housing came out of the barrel adjuster on your brake lever or out of the opening in the caliper and ended up snagged on the edge of the opening. That would account for the firm lever feel. Especially if it felt like "pads making contact" type lever feel and not just a soft "cable drag" lever feel.

    After squeezing the lever a few times the cable housing probably just popped itself back into place making things feel right again.

    I've had that happen to me a few times before in the shop though when the cables were loose. I'm guessing that your cables are too loose and they might "pop out" after landings.

    The first thing I would check is that you don't have too much cable slack. Next try adjusting the return spring on your caliper, maybe it's set too loose. In general when you release the level does it snap back crisply?
    Last edited by NonHands; 09-22-2010 at 11:29 AM.

  7. #7
    mtbr member
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    Quote Originally Posted by NonHands
    Sounds like the cable housing came out of the barrel adjuster on your brake lever or out of the opening in the caliper and ended up snagged on the edge of the opening. That would account for the firm lever feel. Especially if it felt like "pads making contact" type lever feel and not just a soft "cable drag" lever feel.

    After squeezing the lever a few times the cable housing probably just popped itself back into place making things feel right again.

    I've had that happen to me a few times before in the shop though when the cables were loose. I'm guessing that your cables are too loose and they might "pop out" after landings.

    The first thing I would check is that you don't have too much cable slack. Next try adjusting the return spring on your caliper, maybe it's set too loose. In general when you release the level does it snap back crisply?
    yep, I've had the exact same thing happen to me before.

  8. #8
    Dudette
    Reputation: petey15's Avatar
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    The cables/housing were just put on about 2-3 months ago. Okay, I'll check on the things you suggested and report back - thanks for the ideas!

  9. #9
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    had the same exact problem. i thought my lines were catching. replaced them. problem persisted. so i took the caliper apart, and on the lever side, there is a little disc that touches the pad. it is held in place by a retaining ring. turned out that the retaining ring got dirt on it or corroded, and started sticking to the point where the return spring couldn't move back. took it off, problem solved.
    break that ironhorse, he he...

  10. #10
    Davir
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    i think

    Its the barrel adjuster its aligned so the cable is getting caught between it and the locking ring

  11. #11
    Always Learning
    Reputation: BruceBrown's Avatar
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    Quote Originally Posted by NonHands
    Sounds like the cable housing came out of the barrel adjuster on your brake lever or out of the opening in the caliper and ended up snagged on the edge of the opening. ...

    After squeezing the lever a few times the cable housing probably just popped itself back into place making things feel right again.
    I'm going to vote for that scenario. Either the housing slipped out of the ferrule or the ferrule slipped out of the barrel adjuster or the caliper momentarily and after the OP got riding again it popped back into place. It's not that uncommon.

    BB

  12. #12
    rebmem rbtm
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    It happened after a landing.

    - On landing the fork is compressed and the cable housing was pushed up through a zip tie on the crown that stops it flapping about.

    - When the fork extends the cable housing gets momentarily caught on the zip tie which is enough to pull it out of the end of the calliper where it's normally recessed, the end of the cable housing then gets caught on the lip of this part of the calliper instead of going back to it's normal recessed position, this causes the cable to tighten as if the brake was partially applied.

    - The brake lever is pressed afterwards which compresses the cable housing with enough force to pop it off the the lip of the calliper where it was caught and it slides back into it's normal recessed position on the calliper.

    - Brake works as it normally would.

  13. #13
    PVNEMBA vee pee
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    Quote Originally Posted by nepernesu
    had the same exact problem. i thought my lines were catching. replaced them. problem persisted. so i took the caliper apart, and on the lever side, there is a little disc that touches the pad. it is held in place by a retaining ring. turned out that the retaining ring got dirt on it or corroded, and started sticking to the point where the return spring couldn't move back. took it off, problem solved.
    Had a similar issue after a really wet and muddy race. It was good as new after I took apart the caliper and cleaned out all the gunk.

    - Chris

  14. #14
    rebmem rbtm
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    Quote Originally Posted by nepernesu
    there is a little disc that touches the pad. it is held in place by a retaining ring. turned out that the retaining ring got dirt on it or corroded, and started sticking to the point where the return spring couldn't move back. took it off, problem solved.
    That little disc is the Outboard Pressure Foot which is seated in the Drive Cam and held in place with a retaining ring. The Outboard Pressure Foot is the part that moves when you turn the Outboard Pad Adjuster Knob, it doesn't actually move out itself when the brake is applied, it's attached to the Drive Cam which is the moving part.

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