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  1. #1
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    Weak Stopping Power

    I have lower level Shimano mechanical disc brakes. I noticed yesterday that the front brake wasn't biting like the back brake. I squeeze hard going fast enough and I can't get the front brake to skid. It only rolls to a stop. The bike is relatively and only has 160 miles on it so I don't think the pads are worn.

    Could it be the pad alignment? Should the inner pad be closer to the disc than the outer pad? Right now, the outer (moving) pad is closer to the disc than the stationary inner pad. Is this the problem?

  2. #2
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    Quote Originally Posted by SabbathU71
    I have lower level Shimano mechanical disc brakes. I noticed yesterday that the front brake wasn't biting like the back brake. I squeeze hard going fast enough and I can't get the front brake to skid. It only rolls to a stop. The bike is relatively and only has 160 miles on it so I don't think the pads are worn.

    Could it be the pad alignment? Should the inner pad be closer to the disc than the outer pad? Right now, the outer (moving) pad is closer to the disc than the stationary inner pad. Is this the problem?
    It is generally not a good idea to lock the brakes, and an even less good idea to lock the front brake. Ugly crashes happen this way. Trust me, I know.

    When you are pulling on the front brake lever, does it come all the way to the handle bars? If so then you probably have to adjust the barrel adjuster screw on the lever to take out some of the slack on the cable.

    Unless the brakes were being applied full for all of the 160 miles the pads should be fine.

    If the bike was purchased from a bike shop I would advise taking it back to them, and asking them to help adjust the brakes. Watch what the mechanic does and learn about the system that way. Most bike shops are willing to help customers in that way.

    Cant really comment on the pads being closer on one side then the other, not familiar with the shimano mechanical brakes, sorry

  3. #3
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    Quote Originally Posted by 006_007
    It is generally not a good idea to lock the brakes, and an even less good idea to lock the front brake. Ugly crashes happen this way. Trust me, I know.

    When you are pulling on the front brake lever, does it come all the way to the handle bars? If so then you probably have to adjust the barrel adjuster screw on the lever to take out some of the slack on the cable.
    I'm not trying to lock them up, I just noticed that even at 4 mph the bike rolls for about 3-5 yards before I can stop fully. It used to stop harder than that.

    The brake cable tension is fine, I think. The levers dont go all the way to the bar.

    Thanks for the reply

  4. #4
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    Perhaps the pads glazed over? Or maybe contaminants were exposed to the pads and rotor? You can try soaking your pads in alcohol overnight, and then blowtorch them until you burn all the alcohol off (or until it stops smoking if there's oil on it). Then sandpaper your pads and rotors and rinse with alcohol. On mechanicals, the inner pad typically is closer to the rotor because the inner pad doesn't move. The outer pad pushes the rotor into the inner pad and sandwiches it. There are also three bolts on the side of the caliper closer to the wheel. One bolt moves the inner pad closer or farther away from the pad, and the other two hold the two sides of the caliper together. Try tightening/loosening those as neccesary.

  5. #5
    nnn
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    I think your problem is with pad allignment as you said it the passive pad is further out than the active (pressing) pad which means the rotor has to bend to get to the other pad which decreases braking force and you might not be getting contact at all. Basically try to get the passive pad as close to ther rotor as you can to reduce flex and get the best contact from both pads.

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