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  1. #1
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    Marta SL braking issue even after repeated bleeding

    My rear Marta SL (09) is seriously a neverending headache. Ive taken it to two shops now to be bled after trying to figure it out myself, and the problem still wont go away.

    When the lever is pulled, it engages very late in the stroke and gives no power - I cant even lock my rear wheel on pavement. Since it bites so late, I can hit my grip with the lever without even trying and still be wondering why nothing is happening. The pads are almost new.

    Its as if there isnt enough fluid in the system, but both shops are reputable and one worked on it for 2+ hours trying to get it to go. The guy mentioned that it was very difficult to get fluid through the hose, as if there was something blocking it, but he said he managed to work around the problem.

    Anyone have any ideas? Im pulling my hair out here. Thanks in advance!

  2. #2
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    Bleed it here and bleed it there, but sounds like air.

    Try taking the wheel off, pulling the lever until the pads are just close enough so that it looks like the rotor will go back in. Put the wheel back in. (If the pads are too close, then just spread them apart a bit.) This should shorten the lever throw. If you still get a soft and ever mushy pull, then it is probably air. If you can pull the lever a bit with out the pads moving in, it is probably air. At least bleeding is probably the cheapest fix. Even a good shop can get it wrong.

    There is a lot in this forum about bleeding Maguras. Do some searching, but don't restrict the search to just the Marta line up.

    Good luck.

  3. #3
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    Another thing to check is proper caliper alignment. After I bled my Louise rear brake I installed it and didn't notice that I added some extra shims and the outboard pad touched way before the inboard pad and had to bend the rotor over and it made the brake very mushy and it didn't have much power.

    If he really did have that much trouble pushing fluid through it, it may be worth it to replace the hose if you try another bleed and don't get good results.

  4. #4
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    Sounds like a problem I had. Turned out to be sticky pistons.
    Click on this.

    http://forums.mtbr.com/attachment.ph...1&d=1302349138
    Attached Files Attached Files

  5. #5
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    Thanks for the tips. Gave the sticky piston fix a try with a second person and it fixed the squishiness a bit, but its still slightly spongy. The wheel locks now but only under really hard braking when the lever is touching my fingers on the grip.

    Will unsticking the pistons over and over again make any difference, or is going through the process only once supposed to solve the problem?

  6. #6
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    Yes, doing it more than once is probably a good idea. I'd recommend a couple of other things first though.
    With the wheels removed, insert a flat bladed screwdriver between the pads and carefully move them away from each other so they move into the caliper body as far as they will go. Remove the pads and make sure the cylinder bore is nice and clean. I've done this by spraying with electrical contact cleaner, which evaporates fast, but you could do it with water as long as you make sure it dries out thoroughly. Then put two or three drops of Magura mineral oil onto the cylinder bore. ( I use the sharp end of a small cable tie) This is to lubricate the seal around the piston.
    It sounds like you may still have some air hiding in there, so the second thing, while the pistons are fully retracted into the caliper, is to tap the length of the hose with a screwdriver or similar to dislodge any air bubble and help it to the top and into the master cylinder. Air could be hiding in the caliper, and the fully retracted pistons will hopefully force it into the hose. I ended up removing my rear brake and hanging it for a day with the hose vertical, every time I went past I would give it some more taps. It hasn't faulted since.
    Next go back and do the Tech Tipp.

    Hope this helps.

  7. #7
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    If you are gong to try this tapping to move air up and out of the caliper (which I also do during a bleed or before a top off) try some further stuff. Air in the master can still make braking softer, so try to get it into the reservoir (which it sounds like chrisem accomplishes ). Loosen the bake on the bar and swing it a little above horizontal, and tighten slightly. Slowly pull the lever and let it snap back. Do this a few times. This might trap the air in the reservoir. If you notice an improvement and want to try to get rid of this air without a bleed, often you can take the reservoir (having first turned the master horizontal) cap off and top off with a little oil. (But messing with those little screws stresses me out.) Often, the air will stay trapped in the reservoir without a top off.

    Keep us posted.

  8. #8
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    Yeah, do the trick knl2stl describes, as that is very important to get air up to the reservoir, and worked well for me.
    I thought it was mentioned in the tech tipp pdf, but I wuz wrong.

  9. #9
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    Another update to my brake problem:

    The feel is still spongy even after multiple piston resets and bleeds, being very careful to always leave things topped off so fluid is overflowing when I tighten things up.

    Now, the bleed screw on the reservoir cap (the hex bolt, not the three small torx bolts) wont tighten at all, and just spins in place without biting any thread. If I remove the reservoir cap, the screw goes in just fine and tightens up. Ive tried the cap and screw from the front brake and it makes no difference. Its as if the thread for the bleed screw is too deep in the lever body and as a result the bleed screw cant bite it when the reservoir cap is on.

    Lost as to what to do now.. fluid keeps leaking out of the bleed port because the bolt wont tighten!

  10. #10
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    Sorry to hear about the further issue. It sounds like the EBT screw, or worse, the master, lost some threads. Sounds like it is time to call or email someone at Magura. Good luck.

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