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rear brake problem

scazzerscazzer Posts: 254
edited September 2010 in MTB workshop & tech
Im using Deore LX disc brakes and been haveing trouble with rear brake :?

bikes couple years old and about 2 months ago put new pads in and they worked fine for 2-3 weeks then just went shite all of a sudden.....

So thinking i might of contaminated them whilst cleaning and lubing i put another set in and changed mineral oil and rebled only for these to have done the same as last 1's :evil:

Ive just had a look to try and see why and ive noticed on the back of 1 pad there is a spot of oil,so im assuming maybe a seal has gone on 1 piston......so is this possible ?if so is it easily repairable by me or is it a send away jobby??

cheers

Posts

  • nicklousenicklouse Posts: 50,675 Lives Here
    so shite brakes.

    explain?

    why bleed the brakes?

    why did you not clean the rotors if you thought you had contaminated the brakes?

    what does the lever feel like?
    "Do not follow where the path may lead, Go instead where there is no path, and Leave a Trail."
    Parktools :?:SheldonBrown
  • scazzerscazzer Posts: 254
    when i first fitted new pads i bedded them in and they worked like a dream locking back wheel on braking then after 2-3 weeks they were'nt as effective,they start to squeal and wouldnt lock wheel only slow you down slightly..

    Rotors were cleaned each time when new pads went in with isopropyl.

    I bled the brakes as lever was almost touching grip but now only 1inch travel and feels like it should,but concerned that will change if there is a slight leak and im wondering if there is then its possibly getting onto the rotor and contaminating pads..

    hope this explains a bit better :wink:
  • nicklousenicklouse Posts: 50,675 Lives Here
    make sure the disc is not being moved by the pads.

    if there is a leak the lever will come to the bar over time and the lever will feel spongy and will pump hard after a few pulls.
    "Do not follow where the path may lead, Go instead where there is no path, and Leave a Trail."
    Parktools :?:SheldonBrown
  • scazzerscazzer Posts: 254
    just looked at disc and it is being moved but only slightly maybe mm if that.....

    So if it turns out that ive got a leak from a piston is it easy to repair or has it got to be sent away??

    cheers for help
  • nicklousenicklouse Posts: 50,675 Lives Here
    some shimano calipers are not serviceable.

    align the caliper as the disc movement will be pushing the pads back in and make the lever feel poor.
    "Do not follow where the path may lead, Go instead where there is no path, and Leave a Trail."
    Parktools :?:SheldonBrown
  • scazzerscazzer Posts: 254
    ok just re-lined the caliperand gonna fit last set pads in and hopefully goes ok,will keep an eye on piston for any leaks....

    cheers nicklouse for help and time :wink:
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