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Thread: rub

  1. #1
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    rub

    I have the slightest rub on my BB7's...both front and rear.

    I need to listen very hard to hear it, but It's there.

    To get it to disappear, I need to back way off on the pads, which results in squishy lever action.

    Should I put in the time to readjust the entire setup, or is this relatively normal.

    My rotors are true (to the eye while spinning) but they are definitely slightly touching the pads when I hand spin.

    I'm guessing this will equal out after a decent ride...

    what to do?
    2012 Trek Marlin BB7's / SD-7's, G3's, and Kenda Nevegals


    My website: www.n2ovette.com

  2. #2
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    Is it an intermittent noise, like the rotor is out of true? They should straighten themselves out, you are probably worrying about nothing as long as it is not a constant rub. The one thing to make sure is that the pads are completely parallel to the rotor (ie the caliper is positioned properly).

  3. #3
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    Quote Originally Posted by dundundata View Post
    Is it an intermittent noise, like the rotor is out of true? They should straighten themselves out, you are probably worrying about nothing as long as it is not a constant rub. The one thing to make sure is that the pads are completely parallel to the rotor (ie the caliper is positioned properly).
    not constant...just one part of each rotor. They look really straight, so I did not want to go bending anything. I think I will teach myself to live with it...which is difficult for a perfectionist!
    2012 Trek Marlin BB7's / SD-7's, G3's, and Kenda Nevegals


    My website: www.n2ovette.com

  4. #4
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    yes that is totally normal I used to bend them but it's a waste unless they got really out of true somehow. Just ride them and check the pads now and again to make sure there is some clearance.

  5. #5
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    Is the rotor touching both pads at once? Shine a light through the gap to get a better idea. If only the inner pad is rubbing, there's not much you can do other than back it off and get mushy brakes. It's a limitation of the BB7.

  6. #6
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    say what now? I don't see how they are limited. You can adjust the calipers, pads, and rotors to your hearts content.

  7. #7
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    Quote Originally Posted by dundundata View Post
    say what now? I don't see how they are limited. You can adjust the calipers, pads, and rotors to your hearts content.
    Only one pad moves when you pull the lever. With a gap on the inside pad, the whole rotor will need to bend to hit the pad. This will give the mushy lever feeling.

  8. #8
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    OK I see what you are saying but with proper setup this shouldn't be an issue, one may just need to move the caliper itself.

  9. #9
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    As presslab suggested shine a light through the caliper and see where the rotor is sitting. Back the pad out that is touching one click, then turn the opposing pad in one click. Pull the lever a couple of times to set the pads to their new position then spin the wheel and listen for rub. That' how you dial out rub with minimal affect lever feel. If you can't get the rub dialed out without mushing out the lever then you either need to have the rotors trued or you need to redo your set up. Just remember that BB7s, while highly adjustable, do have limits. The tighter you want to run the pad to the rotor the straighter the rotor has to be. What may look visibly true, may not be true enough for the way you want the brakes to feel at the lever. Bottom line is, if you are running your pads very tight to the rotor you may have to put up with a little light rub, or have the rotors precision trued.

    Good Dirt
    "I do whatever my Rice Cripsies tell me to!"

  10. #10
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    The pad piston/holder has a sphere on which it floats so that it may adjust to the angle of the rotor during braking. Both sides are like this. They won't stay parallel to one another.

  11. #11
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    What I mean by parallel is when you are tightening down the caliper bolts to the frame you want them even. So when you are looking at the pad it has the same clearance space on each side (each side of 1 pad if you take my meaning).

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