2008 front brake issues

Discussion in 'Parallel Universe' started by Cavi, Apr 7, 2020.

  1. Cavi

    Cavi Been here awhile

    Joined:
    Apr 22, 2007
    Oddometer:
    344
    Location:
    Red Bluff , Ca
    soo, a couple of weeks ago I went to ride, first time in a couple of months due to winter. Front brake was dead, pull and it goes all the way to the bar and nothing. After maybe 2 blocks some pumping it was fully back. Couple of days latter same thing, so I figured old fluid, got water sucked in and now air. Took to my local mechanic, he bled the system and all seemed well. Well, last weekend I went to ride and again the brake was gone. This time it would not come back. So today I took it back for a final try at bleeding. It again feels fine but I honestly doubt it will stay this way. He and I feel that either the master cyl. needs a rebuild or I have an issue with the ABS (although the rear is fine).
    Ideas? Any idea where I can get a cyl rebuild kit? I did not even manage to find it on the microfiche, and I really did look.
    #1
  2. JRWooden

    JRWooden never attribute to malice...

    Joined:
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    Oddometer:
    7,003
    Location:
    North Carolina
    The BWM factory system and the GS-911, (MAYBE the motoscan I don't know...)
    have a function that pulses the actuators in the ABS unit to help bleed out any trapped air bubbles.
    Did your mechanic have/use one of those?

    If not ... it seems like a cheap thing to try ...
    #2
  3. Cavi

    Cavi Been here awhile

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    344
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    Red Bluff , Ca
    more info please... A link to buy this maybe??
    #3
  4. JRWooden

    JRWooden never attribute to malice...

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    #4
    soldierguy likes this.
  5. Trekka273

    Trekka273 Been here awhile

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    Even if there was a small amount of air in the system, I find it hard to believe that this would result in the lever going to the bar within in a few days. While I guess that it could be an ABS system issue, without seeing what is going on first hand I would be thinking that it is the master cylinder. Perhaps a seal has deteriorated or similar. If so, it should be a relatively easy and cheap rebuild, you would soon know if it didn't fix the problem.
    #5
  6. 211

    211 ThorsPadre

    Joined:
    Mar 5, 2012
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    Bellingham
    You can actuate the ABS with Motoscan professional
    Requires OBDLink scan tool
    adapter cable
    Motoscan (professional version to unlock the usable features)
    Android device to run Motoscan
    #6
  7. Strawdog

    Strawdog Strawdog

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    Location:
    Fannystelle
    If you have air (spongy brake) bleed the master cylinder first. It may take awhile I will loop bleeder hose back into reservoir once clean fluid is coming through. Then do lower brakes. It can what seems like allot of fluid.

    I had had same issue on my F800GS it is difficult sometimes to get air out of the master cylinder. I have a GS-911 did not help air trapped in master cylinder unless you change the ABS pump you should not need GS-911.

    From your description your ABS systen is fine

    On different bikes I worked on brake master cylinders can be a real PIA to bleed
    #7