Leaking Clutch Master Cylinder

Discussion in 'KTM 950/990' started by dwj - Donnie, Jun 4, 2015.

  1. dwj - Donnie

    dwj - Donnie Long timer

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    Hi! :D

    My clutch master cylinder has a small leak where the lever depresses the pin going into the master cylinder. Is there a repair kit for this and a repair tutorial? I cannot find the master cylinder on the Parts Fishe. Thanks!

    Donnie
    #1
  2. unaweep

    unaweep Uses lotsa band-aids

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    I think this is the part number you're looking for. It includes the piston and the seals. Good luck.

    50302032000 REP.SET PISTON MAGURA D=10.5

    The clutch master cylinder is located on the handlebar controls fiche. :thumb
    #2
  3. Lycan1

    Lycan1 Grizzly herder

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    Mine is leaking a little as well and replacing the piston did not fix the problem. Most likely a worn bore in the cylinder.

    I currently have a new cylinder on order from Magura and when it arrives I'll post a link and contact info for you. The KTM part only comes as a complete unit, lever and all and is a bit pricey.

    In the mean time just keep an eye on the level in the reservoir and keep riding, which is what I'm doing.
    #3
  4. dwj - Donnie

    dwj - Donnie Long timer

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    Thank you very much! :clap:clap:clap

    Now, if there is a Tutorial with pictures out there somewhere. :huh
    #4
  5. dwj - Donnie

    dwj - Donnie Long timer

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    Thanks! :clap:clap:clap I am currently in Mexico and will be returning to the US in a couple weeks.
    #5
  6. Lycan1

    Lycan1 Grizzly herder

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    [​IMG]
    Inmate "noregretsallowed" posted this some time ago.

    See here: http://www.ktmsmt.com/viewtopic.php?t=6578

    Once you remove the lever and this "C" clip the white washer and piston assembly just pops out. It helps to have 3 hands when trying to push the new piston and washer in far enough to get the new clip into the nearly invisible slot.
    #6
  7. unaweep

    unaweep Uses lotsa band-aids

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    Gosh- it's so flipping easy- you don't need a tutorial. Be sure to have plenty of clutch fluid- Magura blood or possibly some really light weight suspension oil. You will find the fluid is filthy! I strongly recommend a full flush.

    I have a brain cramp right now and can't think of the proper name, but you'll need those pliers with the points on the end to remove the circlip that holds the piston in.
    #7
  8. dwj - Donnie

    dwj - Donnie Long timer

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    I have the tool. I always use Baby Oil for fluid. When I did a similar repair on the brake master cylinder of a R1100GS, you lightly honed the inside piston wall before installing the new piston. Do you do the same with this?
    #8
  9. unaweep

    unaweep Uses lotsa band-aids

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    I didn't. I've not heard of this practice before. How would you hone the piston wall? Or what would you do it with, I guess is the better question. I'd be afraid of removing material and causing a permanent leak! :arg

    Baby oil works, too. Hope you can find unscented. :D
    #9
  10. dwj - Donnie

    dwj - Donnie Long timer

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    The master cylinder on the BMW was somewhat larger, but the same brand I think. I wrapped some very fine sand paper around a small wood dowel and lightly sanded it. The cylinder wall was rough from oxidation. I removed that roughness and it worked fine.
    #10
  11. unaweep

    unaweep Uses lotsa band-aids

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    Good to know. Thanks.
    #11
  12. gearheadE30

    gearheadE30 @LC8Adventures Supporter

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    I had my master resleeved because after 70k miles of use, it wasn't round anymore and a new piston still leaked. Works great now with the brass sleeve in it, and using light fork oil for fluid seems to have helped a lot as well. Used to run mineral oil in it, and Magura blood before that.
    #12
  13. dwj - Donnie

    dwj - Donnie Long timer

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    Hola! I followed your RR. :D
    #13
  14. unaweep

    unaweep Uses lotsa band-aids

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    Gearhead- how'd you get it re-sleeved? I may be having a similar problem with my SE. Thanks.
    #14
  15. ICERIDER

    ICERIDER Adventure Rider

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    gefr is too polite to chime in here but he has experience of sleeving. Not much help to you right now as he's so far away.

    This problem is a 'stopper' on a long trip so I urge folk to carry a spare assembly complete.

    I'd also like to hear more info on re-sleeving @ 10.5mm which I think is the OEM inside diameter.
    #15
  16. Dusty

    Dusty Long timer

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    Only place i could find that would resleve in the states was ...
    Apple Hydraulics
    #16
  17. unaweep

    unaweep Uses lotsa band-aids

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    Wow. I think I'd buy a new one, first. :dunno

    Thanks for the link. :thumb
    #17
  18. Lycan1

    Lycan1 Grizzly herder

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    I ordered a new one directly from Magura USA. 1-618-395-2200 Peter at ext 223

    http://www.magura.com/en/powersports/catalog.html


    Total cost before shipping was $150.00 vs. $272.80 from KTM.
    This one is a new design by Magura but still a 10.5 mm cylinder and is complete with everything except the correct plug on the clutch switch. The wires were 6 " too short but it was an easy fix splicing the correct end onto the new switch wires.

    [​IMG]

    The color code on the wires on the new unit were blue and black, with the stock; brown and yellow. Black connects to brown and yellow to blue. Tested and working for all functions; won't start in gear without the clutch pulled in and stalls if the side stand is down and the clutch is let out.

    I took it for a short ride and the feel is better than the stock unit, almost as good as a radial unit.

    The reservoir is slightly larger than the stock unit and the mirror mount is a perfect match, although I use a ram ball and double take mirror.

    Pictures;

    [​IMG]
    Old stock unit above.

    [​IMG]
    New Magura unit.

    [​IMG]
    Part Number: 2700185

    Invoice notes; 167.2 LS/ES MASTER CYL LH MIN. 0. 10.5 STREE W/SW+Mirror B.

    No more leaky clutch master and the clutch engagement feel is better than it ever has been. :clap
    #18
    -DeMoN- likes this.
  19. dwj - Donnie

    dwj - Donnie Long timer

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    Thanks! :clap:clap:clap
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  20. gefr

    gefr Life is a trip

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    At what mileage do you get the master cylinder leaking?
    Great find.
    Couldn't you install the old safety switch to the new master cylinder?
    This would eliminate all wiring problems.
    :ear
    Cheer
    #20