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SLX (M675) Brake Squeal and down on power

nadamanadama Posts: 12
edited June 2013 in MTB workshop & tech
Hi I bought some M675 brakes from rose bikes a few months ago. Now every time i use my brakes the squeal horrendously and very low on power. This seems to go by the end of the ride or after a long decent and the power comes back.

I managed to get a half decent bleed on them however they seem to get soft fairly quick.

The front lever also leaks fluid out initially after bleeding for the first few miles when I initially pull the lever.

Any idea what the problem maybe and how I may resolve it.

Thanks

Nathan

Posts

  • cooldadcooldad Posts: 32,599
    A few more details would help - new brakes - how many times have you bled them? They shouldn't have needed any.
    Where does the fluid leak from?
    Did you shorten the cables?
    Have you sprayed/got anything near the rotor?

    Based on what you've said could be the hose isn't connected to the lever properly, letting fluid out and air in.
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  • nicklousenicklouse Posts: 50,675 Lives Here
    squeal and down on power sounds like contamination or glazed.

    clean them and see if it helps or remove. clean the rotors and calipers and fit new pads.
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  • nadamanadama Posts: 12
    Thanks for the replies. I have bled them a couple of times. Initially because I shortened the hoses then again because the bled wasn't very good.
    The fluid leaks out between the main reservoir and top silver cap on the lever. This however seems to improved although not completely gone.
    I have tried cleaning the rotors and sanding the pads down. However when i did a stop again as soon as it got to a slow(ish) speed the squeal was there. (they don't squeal at higher speeds)
    I don't think i have got anything on the rotors but not saying it isn't possible.
  • The RookieThe Rookie Posts: 27,804
    nadama wrote:
    The fluid leaks out between the main reservoir and top silver cap on the lever. This however seems to improved although not completely gone.
    Remove cap, make sure diaphragm is mounted correctly, refit.......I bought some that leaked at that joint, turns out the the diaphragm was twisted out on one side.
    Current steed - Whyte T129, 2013 frame, mongrel Revelations, Giant dropper, Stans S1 wheelset. 12, Magura Trail Sport brakes, 1x11. 12.8Kg
  • nadamanadama Posts: 12
    I have just tried this and it does seemed to have worked.
    Thanks
  • levolonlevolon Posts: 78
    edited June 2013
    nadama wrote:
    The fluid leaks out between the main reservoir and top silver cap on the lever. This however seems to improved although not completely gone.
    Remove cap, make sure diaphragm is mounted correctly, refit.......I bought some that leaked at that joint, turns out the the diaphragm was twisted out on one side.



    good job its not dot4 etc as it could speed up hydration lol
  • levolonlevolon Posts: 78
    edited June 2013
    lon 456 wrote:
    nadama wrote:
    The fluid leaks out between the main reservoir and top silver cap on the lever. This however seems to improved although not completely gone.
    Remove cap, make sure diaphragm is mounted correctly, refit.......I bought some that leaked at that joint, turns out the the diaphragm was twisted out on one side.


    good job its not dot 4-etc as it could speed up hydration !! lol
  • nadamanadama Posts: 12
    Thanks. I have sent them off to rise bikes for the calipers to be sorted. Just hope they come back fixed.

    Thanks for all the replies
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