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  1. #1
    Senior Member
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    Simplex demultilicator? What does it do?

    I remember this coming up in a thread recently. What do they do?

    Anyway, spotted 2 on ebay if someone needs:

    http://cgi.ebay.com/Simplex-Demultip...0#ht_500wt_922

  2. #2
    Senior Member ColonelJLloyd's Avatar
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    Cue Grand Bois in 3...2...
    Bikes on Flickr
    I prefer email to private messages. You can contact me at justinhughes@me.com

  3. #3
    no one cares -holiday76's Avatar
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    thanks for reminding me I needed to buy that $20 one
    Mmmm, bicycles.

    I prefer emails to private messages - holiday76@gmail.com

  4. #4
    Disraeli Gears Charles Wahl's Avatar
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    If I recollect accurately: the Simplex barcons wrap so much cable that it's difficult to find the friction-shifting "sweet spot" unless the demultiplicator is used, so that there's more rotation on the levers between each gear.

  5. #5
    26 tpi nut. sailorbenjamin's Avatar
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    Yeah, the incoming cable joins the lever at a different spot than the outgoing cable so you get a different amount of pull.
    The levers don't give the same amount of pull that the derailler wants so this converts it for you.
    I have spoken.

  6. #6
    Senior Member tugrul's Avatar
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    Does anyone know the ratio?
    Looking for • Quick release for a BR-6208 • Cotter pin press

  7. #7
    Senior Member
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    Quote Originally Posted by Charles Wahl View Post
    If I recollect accurately: the Simplex barcons wrap so much cable that it's difficult to find the friction-shifting "sweet spot" unless the demultiplicator is used, so that there's more rotation on the levers between each gear.
    Doesn't that work in a similar manner to a Shiftmate? If it does, would a shiftmate be useful for the same purpose as the original Simplex demultiplicator, as an in-line kludge for shifter-derailer cable pull issues?

  8. #8
    no one cares -holiday76's Avatar
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    I'll find out soon enough, but what I don't get it how the simplex units pull any more cable than say a campy bar end or even a suntour. I have all of them and mechnically they really seem to be the same.
    Mmmm, bicycles.

    I prefer emails to private messages - holiday76@gmail.com

  9. #9
    no one cares -holiday76's Avatar
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    and btw that guy must have a lot of them because he just relisted another one for $19 right after i bought mine

    http://cgi.ebay.com/Simplex-Demultip...item4aa9726c4c
    Mmmm, bicycles.

    I prefer emails to private messages - holiday76@gmail.com

  10. #10
    Disraeli Gears Charles Wahl's Avatar
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    Yeah, so you can get the demultiplicators in bulk, but who can find the Simplex barcon levers that go with them?

  11. #11
    26 tpi nut. sailorbenjamin's Avatar
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    Quote Originally Posted by -holiday76 View Post
    I'll find out soon enough, but what I don't get it how the simplex units pull any more cable than say a campy bar end or even a suntour. I have all of them and mechnically they really seem to be the same.
    Maybe it's the derailler that needs less than average pull?
    I have spoken.

  12. #12
    no one cares -holiday76's Avatar
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    Quote Originally Posted by Charles Wahl View Post
    Yeah, so you can get the demultiplicators in bulk, but who can find the Simplex barcon levers that go with them?
    wasnt too hard to find the set I have if I remember correctly. They arent the retrofriction ones though.
    Mmmm, bicycles.

    I prefer emails to private messages - holiday76@gmail.com

  13. #13
    aka Tom Reingold noglider's Avatar
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    I understand why it does this but I don't understand how. Please explain it so even I can understand.
    Please email me rather than sending me a private message. My address is noglider@pobox.com

    Tom Reingold
    Residences: West Village, New York City and High Falls, NY
    Blogs: The Experienced Cyclist; noglider's ride blog

  14. #14
    Senior Member Michael Angelo's Avatar
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    Quote Originally Posted by dbakl View Post
    I remember this coming up in a thread recently. What do they do?

    Anyway, spotted 2 on ebay if someone needs:

    http://cgi.ebay.com/Simplex-Demultip...0#ht_500wt_922

    Mechanical advantage. At the pivot point you have a lever with two cable stops with two different lengths. The rear lever(shorter) moves farther than the front lever (longer)for the same amount of movement.

  15. #15
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    perhaps best to comprehend by illustration, see sketch (third picture):

    http://velobase.com/ViewComponent.as...m=103&AbsPos=5

  16. #16
    Senior Member Grand Bois's Avatar
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    Quote Originally Posted by ColonelJLloyd View Post
    Cue Grand Bois in 3...2...
    I've given up trying to explain it.


  17. #17
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    Quote Originally Posted by Grand Bois View Post
    I've given up trying to explain it.

    Does it DECREASE or INCREASE the pull? Not playing dumb, just never seen one!

  18. #18
    Senior Member Michael Angelo's Avatar
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    It pulls more cable at the back side, so it increases the pull.

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