Master cylinder front brake bleed

Discussion in 'GS Boxers' started by das Motorradreiter, Jan 21, 2013.

  1. das Motorradreiter

    das Motorradreiter Diehard Extraordinaire

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    2004 R1150GS
    I removed the ABSi system due to a servo failure and converted my brakes to standard a little while ago.
    Today, I ordered new lines from Spielger but just now thought of something - My bike has no master cylinder bleed nipple.
    Will I have a problem getting all of the air out of the lines without one? I ask this because I have always bleed my own brakes annually over the years but never had to start from scratch with a dry system which is what I will be doing after I replace the lines.

    Every video I have seen online shows a tech utilizing a master cylinder bleed screw which my bike does not have. Would buying one of those MityVac things prevent any problems?

    Thanks for any input.
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  2. JimVonBaden

    JimVonBaden "Cool" Aid!

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    Nah, just bleed as usual. If you gut smooshy brakes, tie off the handle overnight to hold the pressure on and the bubbles will rise up to the MC.

    Jim :brow
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  3. das Motorradreiter

    das Motorradreiter Diehard Extraordinaire

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    Sounds good, Jim.

    What about reverse bleeding it with one of those large syringes down at the caliper?
    I've always wondered about getting one of those set-ups so I don't have to call upon my wife for brake bleeding.
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  4. JimVonBaden

    JimVonBaden "Cool" Aid!

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    I have never tried it, but some report very good success doing it.

    Jim :brow
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  5. Mike Figielski

    Mike Figielski Been here awhile

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    I like using the syringe along with traditional bleeding. Helps get some of the stubborn bubbles. May need to bleed a banjo bolt or two by cracking them open with the lever held. A little messy but works. So does Jim's suggestion to strap the lever down overnight. Good luck!
    Mike
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  6. Twilight Error

    Twilight Error Going nowhere slowly

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    I've done it several times, its quite easy and very effective. I use a disposable 100cc luer lock syringe obtained from the vet I take my cats to.
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  7. das Motorradreiter

    das Motorradreiter Diehard Extraordinaire

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    I visited a local farm supply store and got a Monoject luer lock 60cc syringe for $1.99.
    I found an old length of tube from Progressive Suspensions sitting around that just happen to have the threaded plastic gizmo which adapts to a luer lock. Bonus - The tubing fits a caliper bleed screw nicely.
    I secured the tubing to the luer lock thingy a tad tighter with a small zip tie and tested the set-up with some old brake fluid - no leaks under pressure.
    I now anxiously await the delivery of the Spiegler package.
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  8. Twilight Error

    Twilight Error Going nowhere slowly

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    Perfect.

    When you fill the system, pull just a little less fluid than the capacity of the syringe. This is very important if you've got to push more than once, it gives you just a little space to pull the air pocket formed with the replacing of the hose back into the syringe. And, as per usual, cover the master with something because its easy to misjudge the velocity of the fluid when it enters the reservoir.
    #8
  9. das Motorradreiter

    das Motorradreiter Diehard Extraordinaire

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    Thank you for the filling tip.

    Two questions - Should I start on the caliper furthest from the master cylinder?
    At what point do I switch to the other caliper?
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  10. Twilight Error

    Twilight Error Going nowhere slowly

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    I don't think it matters, both lines have to be filled. I switch to the other caliper when I've got some fluid in the reservoir. If you fill the reservoir with the first caliper, you'll have to draw some out to prevent overfilling when you do the second. Once you've got a firm lever, finish filling the reservoir directly from the bottle and call it good.
    #10
  11. das Motorradreiter

    das Motorradreiter Diehard Extraordinaire

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    10-4. Thanks.
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