ATF fluid in master cyl?

Discussion in 'Crazy-Awesome almost Dakar racers (950/990cc)' started by beergut, Mar 14, 2013.

  1. beergut

    beergut Thumper

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    Im doing my daily check of the 'what did you do to your KTM today' thread and there is some discussion about using synthetic ATF or fork oil in the master cyl/clutch system.

    Are there any benefits to using this instead of the recommended mineral oil? Seems we are talking about apples and oranges here...mineral oil and ATF fluid...

    http://advrider.com/forums/showthread.php?t=568535&page=500
    #1
  2. henryroten

    henryroten Been here awhile

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    I have been told that ATF or fork oil doesn't contaminate as quickly (mineral oil turns black pretty quickly) and some people say that there is better clutch 'feel'. I think that it all got started with the high price of Magura Blood which got folks looking for alternatives.
    #2
  3. Yellow Pig

    Yellow Pig Allergic to Asphalt!

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    Available at most gas stations.
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  4. Katoom72

    Katoom72 Been here awhile

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    It's cheaper. Fork oil works aswell.
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  5. beergut

    beergut Thumper

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    I might have to check this out and give it a try
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  6. roookie1

    roookie1 Been here awhile

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    I have been using 2,5 W fork oil in my Clutchmaster for years now, no probs
    #6
  7. wcohl

    wcohl Been here awhile

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    I've been using whatever weight fork oil (usually 5, but sometimes 10 wt.) fork oil in my Magura MC since 1999. It still has the original master and slave seals. This particylar KTM has seen it's share of mud and water.
    #7
  8. traveltoad

    traveltoad Aaron S

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  9. Greenflyfarmer

    Greenflyfarmer I'm better now.

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    I've used ATF in my 990 and 625 sxc for a several years. I haven't thought about it in awhile. You'll never know the difference in the feel.
    #9
  10. MortimerSickle

    MortimerSickle Semi-Adventurer

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    Some folks will tell you that it is inferior, but in over five years of use, I have yet to find a problem with it.
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  11. Katoom72

    Katoom72 Been here awhile

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    +If u have skin issues on the trip u can open the mastercilinder.... :wink:
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  12. DSM8

    DSM8 Where fun goes to die....

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    The fork oil is a lighter weight than the ATF fluid.
    For that reason I use the fork oil. It lasts longer and does perform better for long time.
    #12
  13. Zuber

    Zuber Zoob

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    ATF is about 7wt, baby oil is much thicker than Magura Blood, I found it to be too thick and didn't like the clutch action.

    I like the 2.5wt fork oil, it is intended for hydrolics and lasts a long time.
    #13
  14. Nailhead

    Nailhead Free at last!

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    I have: there is a slight bit more drag to the clutch action, if that makes any sense.
    #14
  15. zedtours

    zedtours Been here awhile

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    I assume it has to be non synthetic fork oil?
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  16. beergut

    beergut Thumper

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    I dont want to sound like a sissy but there is a lot of drag/pull on my clutch lever and I think it might stem from mineral oil. I will be flushing mine for some fork oil this weekend.
    #16
  17. DSM8

    DSM8 Where fun goes to die....

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    Actually I am running the syth stuff myself for over 10K miles.

    It holds up well, does not degrade due to the heat like the mineral oil does and the performance is still the same.

    Just my .02
    #17
  18. rattis

    rattis Long timer

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    Do they mix or do you have to bleed out the old stuff first?
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  19. sabink

    sabink Been here awhile

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    I use 5w full synthetic fork oil without any problem. I have also mixed with ATF in location where I cannot get fork oil.
    #19
  20. DSM8

    DSM8 Where fun goes to die....

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    If you have mineral oil then it is just a good idea to flush and refill.

    You can prolly mix diff fork oil if you had too but I would try to keep stuff in the same family. ATF, Mineral, Fork etc etc
    #20