Ever wonder about fork oil?

Discussion in 'Thumpers' started by meat popsicle, Nov 19, 2007.

  1. meat popsicle

    meat popsicle Ignostic

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    Obviously I'm lazier Luke! :rofl

    Now if I can finish these KSAs so I can get out to the garage to tear my bike apart some more...
    #41
  2. invader

    invader Adventurer

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    Amsoil's Shock Therapy Suspension Fluid #5 Light does have a viscosity that is comparable to the average of other 5W fork oils: 4.4 cst @ 100°C, and 15.7 @ 40°C.
    Amsoil Medium #10 (10W): 7.3 @ 100°C, 32.1 @ 40°C.

    http://www.peterverdonedesigns.com/files/suspension%20oils.pdf

    Forks typically operate at about 26°C (78°F) in 21°C (70°C) ambient temperatures...
    #42
  3. meat popsicle

    meat popsicle Ignostic

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    hey look a chicken!!! :clap
    #43
  4. wrk2surf

    wrk2surf on the gas or brakes

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    is it fighting with another one???

    seriously if you folks are talking "fork oil" you are using a oil intended for a conventional old school forks... do yourselves a favor when buying for USD and get FORK FLUID...


    look a jackalope
    #44
  5. ChrisC

    ChrisC Amal sex?

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    Fuck me... a ancient thread resurrected, dealing with oil, and an Amsoil recommendation.

    It's a goddamn trifecta. :freaky
    #45
  6. meat popsicle

    meat popsicle Ignostic

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    Actually (with my most posh Brittish accent)... that would be SUSPENSION FLUID. :jive

    If you were an engineer you would call it HYDRAULIC FLUID (because that is what it does).

    And if he wasn't selling AMSOIL he would have given us the VISCOSITY INDEX.

    There's your TRIFECTA MOFO! :smooch
    #46
  7. ChrisC

    ChrisC Amal sex?

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    [​IMG]
    #47
  8. Beezer

    Beezer Long timer Supporter

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    my .02 dollars..... I switched to ATF a couple years ago & it seems to work fine. I did a bunch of timed flow tests with a 20cc pipett, and Chevron synthetic ATF seems to be really close to 10 wt Belray viscosity wise... and mixed 50/50 with Marvel Mystery Oil it is the same as 5 wt Belray.
    #48
  9. ChrisC

    ChrisC Amal sex?

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    I would prefer Amsoil Mystery Oil... or is it Mystery Fluid??? Meat!
    #49
  10. meat popsicle

    meat popsicle Ignostic

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    Excellent Beezer - now repeat your experiment but vary the temperature with each trial, maybe using the following:

    room temp (stipluate plz)
    50 C
    100 C
    200 C
    300 C
    WAIT!!! Check the products MSDS to ensure you do not exceed the FLASH POINT (temp) of the liquid. Cease and desist well before that temp is reached.

    Viscosity can vary with temperature, which would give the product a low Viscosity Index score, because as your forks heat up, the products viscosity changes, and your forks behavior will change. And you'd like that to stay constant eh?

    A good fork/shock suspension fluid's (aka fork oil) viscosity will not vary much with temperature, allowing your forks/shock to behave similarly no matter what temperature they are (and with all that friction they will vary quite a bit regardless of the ambient temps).
    #50
  11. meat popsicle

    meat popsicle Ignostic

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    We can call Amsoil's fork oil just that, a lubricant with hydraulic properties, until we know its VI. If it's VI is at least 150 we can then decide if it is actually a suspension fluid, also known as a hydraulic fluid with lubricant properties.
    #51
  12. B-Mac

    B-Mac Aged Beef Supporter

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    In the Aviation World, We would call the Front Forks: Dampers and we use Hydraulic Fluid Mil-H-5606 or Mil-F-83828 (Fire Res. Syn.) Check PN for proper Seals :deal Just Saying, M"kay
    #52
  13. meat popsicle

    meat popsicle Ignostic

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    Get down wit'yer bad self! :jive
    #53
  14. swingset

    swingset Got the knack.

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    I just pour more red stuff in when it comes leaking out.

    :freaky
    #54
  15. invader

    invader Adventurer

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    Viscosity index of Amsoil's synthetic "Shock Therapy Suspension Fluid #5 Light" is 210 (Flash Point: 347°F, Pour Point -60°F), and the #10 Medium is at 205 (Flash Point: 396°F, Pour Point -54°F).

    http://www.amsoil.com/storefront/stl.aspx

    http://www.amsoil.com/storefront/stm.aspx

    I don't sell it, but you can get any Amsoil product from http://www.woodsbrosracing.com/amsoil-online-store.htm at over 20% off with the secret promo code.

    I'm currently using Motul's synthesis "Expert Fork Oil " 15W in the Versys. Viscosity Index is only 116 (112 for 5W and 10W, 111 for 20W)... Motul's synthetic "Factory Line Fork Oil" (2.5W, 5W, 7.5W and 10W) has a viscosity index ranging from 112 to 131.

    http://www.motul-canada.com/en/products/products_info/Fork_and_Shock_Oil/Fork_Oil_EX_5W_Light/Fork-Oil_Expert_TDS.pdf

    http://www.motul-canada.com/en/products/products_info/Fork_and_Shock_Oil/Fork_Oil_FL_2_5W_VeryLight/Fork-Oil_FactoryLine_TDS.pdf
    #55
  16. Sparrowhawk

    Sparrowhawk Long timer

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    I have no idea how Amsoil will work in my forks and I do not intend to find out. Why???

    I've gotten 350K miles out of an '64 Ford Econoline with a 170 six, shag carpet, and a fold down bed (a fine vehicle for a college student indeed!), 225K out of a '77 VW Microbus, 87K from a '77 BMW R100, 250K out of a VW Rabbit diesel, 210K from a '87 Toyota van, 185K and counting from a '90 Subaru Legacy, and 22K and counting from a '00 KTM 640 LC4E - all using Mobil 1 once it became available in '74. Never did any significant engine work on any of these rides. I believe in the power of synthetic lubricants. Can I hear an amen?

    But I used Amsoil in a rear differential and within a month my rear wheel bearings failed, leaving me stranded on the freeway. Have you ever tried to hitchhike with long hair and beard, a rear axle in one hand and your thumb out in the other? I used Amsoil in a manual transmission and within two weeks the seals started leaking on to my clutch and I had to replace the clutch plate and tear open my tranny. As a less than wise man once said "There is an old saying in Tennessee - I know it's in Texas - that says; fool me once, shame on ... (blank stare and pause :doh ) ... shame on you. Fool me, you can't get fooled again."

    Your mileage may vary but my experience has firmly placed Amsoil in the same category as Marvel Mystery Oil, Slick 50, Tufoil, STP, and other shéyóu. No thanks!

    Smile and grin at the change all around me
    Pick up my guitar and play
    Just like yesterday
    Then I'll get on my knees and pray
    We don't get fooled again
    Don't get fooled again
    No, no!
    #56
  17. meat popsicle

    meat popsicle Ignostic

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    #57
  18. slideways

    slideways España

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    +1 on the Redline.

    I mix the 5wt and the 2.5 wt 50/50 for the forks on my ktm. This gives a nice plush feel to the forks and helps eliminate the mid stroke harshness.
    #58
  19. michael1968

    michael1968 Long timer

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    Now that's funny.
    #59
  20. web037

    web037 Been here awhile

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    Well, when I changed out my fork springs a couple months ago I put in Maxima 10wt which is clear then I helped a friend do his after that and he used Belray and it was green. Since my bike is white and his is blue did we make the right choice? :rofl
    #60