R1150 GSA 2004 Clutch Slave Cylinder replacement- PICs

Discussion in 'GS Boxers' started by acupuncture4u, Jun 7, 2008.

  1. johnjen

    johnjen Now, even more NOW!…

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    Great write up. If the acupuncture4u is OK with this, I'll add this to the HoW after this thread gets quiet.

    JJ
    #21
  2. JimVonBaden

    JimVonBaden "Cool" Aid! Supporter

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    Not 100%, if it happens again after a total flush, then very likely. Also make sure the line to the slave isn't badly rusted.

    Jim :brow
    #22
  3. AntonLargiader

    AntonLargiader Long timer

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    Yes. If it's merely dark but not cloudy you could change the fluid and see how it goes, but if it looks muddy you need to replace the slave cylinder. It's a closed system and that mud only comes from one place.
    #23
  4. hogmolly

    hogmolly Dude

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    On a R1200GS class bike, the clutch reservoir holds a dark mineral oil. Dark is normal. On the R1150GS class bike, the clutch uses Dot4 which should be clear.
    #24
  5. acupuncture4u

    acupuncture4u Freedom by knobbies

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    If it's quiet enough your welcome to add this to the How to section.

    Dustin
    #25
  6. JimVonBaden

    JimVonBaden "Cool" Aid! Supporter

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    Unfortunately that is not always true. Mine, and many that I am familiar with are a clear fluid.

    Jim :brow
    #26
  7. hogmolly

    hogmolly Dude

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    I didn't know that. Interesting.
    #27
  8. attila_66

    attila_66 Been here awhile

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    Hello,

    Did anyone tried to repair the old slave cylinder??
    #28
  9. Mr Head

    Mr Head Adventure Hippie Supporter

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    Very nice write up.

    My slave was replaced at 97,000 miles but the clutch pull has been getting stiffer here of late, so I'm thinking this is that bearing beginning to go tits up.

    Your write up bouys my resolve to attack this sooner rather than out there somewhere on the road...:rofl

    I bought a bleeder nipple to replace that stupid fitting BMW use when they build the bike. That makes bleeding the clutch a one-man operation. My local dealer had the part in-stock.
    #29
  10. strikingviking

    strikingviking Long timer

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    I have a similar problem with clutch line fluid disappearing with no sign of external leakage. It appears best to replace the slave unit just to be safe. Since the clutch is not yet slipping and there has not been a significant loss of fluid, while replacing the slave unit, would it be possible to spray brake cleaner onto the clutches and then drill a weep hole for draining whatever has accumulated?
    Thanks
    Glen
    #30
  11. Poolside

    Poolside Syndicated

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    <BR>
    There's a felt 'collar' on the push rod, p/n 23 21 1 230 440. As well as an amount of empty area between the push rod OD and the input shaft ID. Since there hasn't been much fluid loss, it may have collected around the push rod and collected in the felt. Maybe you can clean the fluid out with cotton batting and rifle cleaning tools, or cotton balls and a coat hanger. Either way, the clutch friction surface isn't in the centrifugal 'sling path' from the end of the input shaft. And another caveat, hydraulic fluid on organic friction components makes them grabbier. At least that's what happened to every drum brake with a blown slave cylinder I've driven. The wheel locks right up.

    - Jim

    <BR>
    #31
  12. strikingviking

    strikingviking Long timer

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    So what causes the clutch to start slipping then? According to posters here and on other threads, brake fluid seeping past worn slave units eventually made their clutches fail.
    #32
  13. Poolside

    Poolside Syndicated

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    <BR>
    Sorry for the late reply. I thought I already had.

    Clutches can be operated wet, or dry. In lubricating oil, or hydraulic fluid. There are different clutch friction materials, but all can used wet or dry.

    'Modern' materials are sometimes used for clutch friction surfaces. Carbon fiber, Kevlar, etc. But clutches have been operated wet, and dry, long before material science was born. The new materials can also be used wet or dry. Some work a little better dry, others a little better wet.

    Uneven oil distribution can cause uneven clutch wear. Say just a spot or two of a clutch surface gets wet, while the remaining surface stays dry. That area will become a 'high spot'. If a clutch becomes partially wet, the solution is to fully wet it.

    <BR>
    #33
  14. strikingviking

    strikingviking Long timer

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    Thanks again. I just now returned from Mexico and have the part in hand for replacement. Trouble is though, the clutch has started slipping and I sure don't want to have to replace that. I'll try the above cleanup as suggested, install a new slave cylinder and see what happens. Maybe that fluid will boil of the plates and all will be well? Or are they permanently shot? The bike only has 39,000 miles of on-road riding so there shouldn't be much wear.
    #34
  15. tagesk

    tagesk Tuscan rider

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    Added this to the GSpot FAQ, Section 3.

    [TaSK]
    #35
  16. Poolside

    Poolside Syndicated

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    'Install the slave cylinder and see what happens' seems like the only available path at this point. Without removing the gearbox that is.

    A wet clutch runs in some type of operating fluid. The operating fluid which can be motor oil, ATF, etc., soaks into the clutch and swells the fibers a tiny bit, this is normal. But if you started with a dry disk, and only wet a portion of the friction surface, that makes a high spot. The small high spots carry more of the load.

    I guess if I were stranded in BFE (literally), and had tools but no clutch disk, I'd pull the clutch disk and soak it in clutch fluid. But hey, your the daring adventurer, in that situation I may just wet my pants.

    Here's some wishful thinking. Maybe detritus from the worn out seal packs in behind the slave cylinder piston? Or... The slave cylinder has a throw out bearing built into it, maybe bits and pieces from a nerfed throw out bearing get under the clutch rod cup and won't let the clutch rod retract fully. It's a guess, but it's a hopeful guess.

    <BR>
    #36
  17. maalstroom

    maalstroom Ferret Legger

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    would it be possible to spray brake cleaner onto the clutches and then drill a weep hole for draining whatever has accumulated?

    Recently a friend with an R1150R had his slave cylinder replaced by Hank (formerly of Rhinewest). That is exactly what Hank does in most situations, not the brake cleaner, but the weep hole.

    NEECKB
    #37
  18. strikingviking

    strikingviking Long timer

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    Thanks--two questions:
    1. Where exactly to drill the weep hole?
    2. If draining the excess fluid will the residue boil off while intentionally "riding the clutch?" I have accidentally contaminate brake pads before and then just got on a long steep hill to overheat them and bingo, all fluid boiled off.
    #38
  19. firefighter217

    firefighter217 Beerventurer

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    After reading this thread... It was worth every penny Hank took from me!:bow

    The weep hole is a great idea to prevent further damage (as Hank described as Clutch slippage, Striking V.)... according to Hank that little piece of felt will only buy a little time, but once the slippage is present the problem is a bit more complex. Hopefully your seals aren't toast!
    #39
  20. firefighter217

    firefighter217 Beerventurer

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    Call Hank for the exact drill location:

    http://www.motohank.com/BMW%20MC%20Service.html

    I hear he makes "house calls" to Mexico! :lol3
    #40