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  1. #1
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    High Ratio 2 Chain Design?

    Here's a random idea we had. Has anyone seen this before? The idea is to have a ridiculously high gear ratio on a fixed bike by inserting a second chain and third sprocket.

    Your thoughts?

    2-chainer.jpg

  2. #2
    Senior Member Shimagnolo's Avatar
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    http://www.canosoarus.com/08LSRbicycle/LSR%20Bike01.htm

    Note the intermediate shaft is behind the saddle.

  3. #3
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    Nice! Thanks.

  4. #4
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    Also used on high speed recumbent bikes:

    http://www.popsci.com/diy/article/20...s-fastest-bike


  5. #5
    Roadmaster Snobbery Club bhtooefr's Avatar
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    And delta trikes and quads use that method a lot, too, with the IGH as a mid-drive.
    2011 TerraTrike Path 8
    2002 Dahon Boardwalk 1 (with 1976 F&S R 2110 2-speed kickback hub)

  6. #6
    Pedaled too far. Artkansas's Avatar
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    Quote Originally Posted by dfinch View Post
    Here's a random idea we had. Has anyone seen this before? The idea is to have a ridiculously high gear ratio on a fixed bike by inserting a second chain and third sprocket.
    A Giant Stiletto is already set up to do that. You just change the gear.

    "He who serves all, best serves himself" Jack London

    Quote Originally Posted by Bjforrestal View Post
    I don't care if you are on a unicycle, as long as you're not using a motor to get places you get props from me. We're here to support each other. Share ideas, and motivate one another to actually keep doing it.

  7. #7
    I WILL BE YOUR LARRY arex's Avatar
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    I wonder how much extra drag is introduced?
    "Ahab knew, baby...I lust." -- Vet-san

  8. #8
    Uber Goober StephenH's Avatar
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    You didn't say why you'd want to do that. Take a regular road bike, put it in high gear front and rear, and you can't hardly get it started. So you have the potential to make a rather useless gearing system.

    Note that if you're after maximum speed, you need to have it where your legs are spinning at the optimum speed for the most power, not doing leg-press exercises at slow speed.
    "be careful this rando stuff is addictive and dan's the 'pusher'."

  9. #9
    Senior Member Flying Merkel's Avatar
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    This is Alt Bike land where we are unencumbered by sense & reason. Looks cool, good enough reason for me.
    Pronounced "Murkle"

  10. #10
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    Another example of mid-drives is when people build velomobiles or cargo trikes, and they want a wide range of gear ratios but also want to be able to shift gears while standing still.

    Using two internal-gear-hubs (the second one as a mid-drive) gives that ability, and still doesn't cost a great deal of money.

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