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Thread: 2012 R1200RT clutch vs brake res color

  1. #1
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    2012 R1200RT clutch vs brake res color

    Greetings all.
    There I was enjoying a nice ride on my RT when I noticed what a wonderful color of amber my brake fluid made in the resiviour. Then I looked over at my clutch res and it looked black. Momentary panic as usually black brake fluid is bad news, but then I recalled that the clutch uses mineral oil and perhaps has a darker tinted resiviour. But dang me I cannot remember. Find it hard to believe a master going South at almost 4000 miles so I am hoping someone out there with an RT can go look at their's and get back to me.
    Thanks
    Will
    Will Stagg Central Coast of Commiefornia
    2012 R1200RT (most awesome unit)
    1978 R100/7 (sidecar tug )
    Yamaha TW200 adventure bikes (3) waay fun units

  2. #2
    Registered User b25bsaboy's Avatar
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    Will

    1. The clutch fluid recommended is Vitamol V10. The fluid in the reservoir turns black/brown because it's exposed to sunlight which causes over time to breakdown and discolour.

    2. DOT 4 Brake Fluid. The DOT 4 shouldn't damage your seals if used in the clutch system! But is not recommended. Normally any damage is usually caused by dirt and debris getting pulled into the seals as the clutch pistons stroke in and out. Again, the dis-coloration is caused (theory only) by sunlight and moisture getting into the fluid.
    Last edited by b25bsaboy; 11-15-2012 at 12:18 PM.
    Rick MacPherson
    Success is Not a Destination, But a Journey.
    Accredited Motorcycle Appraiser
    1968 BSA Starfire, 1976 BMW R75/6, 2009 R1200RT

  3. #3
    Registered User mneblett's Avatar
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    Quote Originally Posted by b25bsaboy View Post
    DOT 4 Brake Fluid. The DOT 4 shouldn't damage your seals if used in the clutch system. Normally any damage is usually caused by dirt and debris getting pulled into the seals as the clutch pistons stroke in and out
    I strongly disagree with the above!

    First, everything I've read says DOT 3/4 and the mineral oil BMW uses are NOT interchangeable -- seal issues, etc.

    Second, mineral oil is not significantly hygroscopic, unlike brake fluid -- one of the primary reason BMW switched from brake fluid to mineral oil in the clutch circuit (which doesn't see the temps brake fluid can potentially see). The lack of significant hygroscopic concerns is why the clutch does not have a change interval like the brake systems.

    Third, I also have a 2012 R12RT, and without backlight, the clutch reservoir looks much darker than the brake reservoir -- but with a flashlight at the back of the reservoir, the fluid is green and not cloudy (color affected by the yellow plastic reservoir; IIRC, the mineral oil is a fairly deep blue (blue+yellow=green).

    I'd suggest checking with a flash light to see whether you have any real problem -- unlikely on such a new bike.
    Mark Neblett
    Fairfax, VA
    #32806

  4. #4
    Benchwrenching PGlaves's Avatar
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    Just to reiterate, DOT 4 in the clutch system designed for mineral oil will destroy the seals, invade the bell housing, foul the clutch a maybe destroy the transmission input shaft seal.

    The converse is also true - mineral oil in a clutch system designed for DOT 4 will destroy the seals and foul the clutch. It won't damage the input shaft seal which is already exposed to petroleum in the transmission. But by then you won't care.

    At a shop, something north of $2,500 to clean up this little mistake.

    Don't do it.
    Paul Glaves - "Big Bend", Texas U.S.A
    "The greatest challenge to any thinker is stating the problem in a way that will allow a solution." - Bertrand Russell
    http://www.bigbend.net/users/glaves

  5. #5
    Rally Rat
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    On my 12 R1200R the brake fluid was almost brown when I bought the bike. Its now almost clear yellow. I think from the sun. I can't see the clutch fluid in the reservoir. It is full.

    Brake fluid works with rubber seals.

    Mineral oil works with neoprene (plastic) seals.

    Brake fluid attacks plastic, Mineral oil makes rubber swell up and disintegrate.

    Please do not mix them.

    David

  6. #6
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    Color was the question

    Hey fellow enthusists
    I never contemplated adding inappropriate fluids to my brake or clutch systems. Only an ignoramus would consider such. I just wanted to confirm the clutch resiviour was darker in color than the brake res.
    Thanks for the responses!
    Will Stagg Central Coast of Commiefornia
    2012 R1200RT (most awesome unit)
    1978 R100/7 (sidecar tug )
    Yamaha TW200 adventure bikes (3) waay fun units

  7. #7
    Registered User toooldtocare's Avatar
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    My fluid colors are different too. When I shine a light through the cylinders I find the brake fluid is amber, as expected. However the clutch fluid is a pretty shade of green.

  8. #8
    Cam Killer marchyman's Avatar
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    Quote Originally Posted by DROOT153718 View Post
    On my 12 R1200R the brake fluid was almost brown when I bought the bike. Its now almost clear yellow. I think from the sun. I can't see the clutch fluid in the reservoir. It is full.
    Subject drift... if your clutch reservoir is full you may need to remove a bit of fluid. The level rises as the clutch wears. Rising above the MAX mark is not a good thing. I find I have to remove a small bit of fluid about every other service.

    I follow the Tom Cutter method:

    Just twist up a Bounty Paper towel (the Quicker Picker Upper) and use the twisted towel to absorb up a little fluid. It is tidy and economical. Be sure to select a towel pattern that will not clash with your paint job or wardrobe. In the Summer, I prefer light, fun colors.

  9. #9
    Benchwrenching PGlaves's Avatar
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    Quote Originally Posted by arbolmano View Post
    Hey fellow enthusists
    I never contemplated adding inappropriate fluids to my brake or clutch systems. Only an ignoramus would consider such. I just wanted to confirm the clutch resiviour was darker in color than the brake res.
    Thanks for the responses!
    No you didn't. But a poster, in response to your question, explicitly stated that such would be OK. My response was to protect any readers, or future readers who find this thread in the interwebland maze from making a $2,500 mistake. I often let misinformation pass, but not when it involves personal safety or as in this case, big dollars.
    Paul Glaves - "Big Bend", Texas U.S.A
    "The greatest challenge to any thinker is stating the problem in a way that will allow a solution." - Bertrand Russell
    http://www.bigbend.net/users/glaves

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