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  1. #1
    Twincities MN kuan's Avatar
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    Someone should make a gear reducer hub

    Like an old VW Bus final drive. Get off the bike, flip a lever for flat mode or hills mode.

  2. #2
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    Have you ever heard of a company called Sturmey-Archer? They have been making a product like this for, oh... almost 100 years. It's got a gear for the flats, a gear for the uphills, AND a gear for the downhills! You don't even need to get off the bike to actuate it!

  3. #3
    Senior Member staehpj1's Avatar
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    Not a hub, but the Schlumpf Mountain Drive works kind of like that...
    http://www.pbwbikes.com/product_info.php/products_id/59

  4. #4
    Twincities MN kuan's Avatar
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    LOL! That Sturmey Archer would mean three shifters on a bike. But it's good and inexpensive. That Schlumpf is pretty expensive but sure looks like it works.

  5. #5
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    Isn't that the point of your regular gears?

  6. #6
    Senior Member BikeManDan's Avatar
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  7. #7
    Member AbueloLoco's Avatar
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    I have a SRAM dual drive on my bike friday with a 7 speed rear cassette and a three speed internal also in the hub. I don't know of a reason one couldn't put a double or triple chain ring on the front too. I am no techie, so there may be a reason not to. How much gearing one needs is another question altogether.
    Mike - aka Abuelo Loco de Lola & Lance

  8. #8
    Twincities MN kuan's Avatar
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    Quote Originally Posted by Wyzard360 View Post
    Isn't that the point of your regular gears?
    Not enough when you have to drag a kid in a trailer plus both people's gear.

  9. #9
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    That could be done with a planetary gear set in the rear hub without to much trouble.It would work like the old hand crack pencil sharpeners on the inside,same principle(remember those).Instead of a hand crank,the cluster would drive the sun gear.That would give you 27%-33%,up or down,depending on which way you ran it.It would triple(guessing)the weight and diameter of the hub.You would have to make it big enough to fit a sun gear and a set or two of orbiting gears.You wouldn't even need a cable,you could reach in the hub with an allen wrench and turn it 180 degrees to engage/disengage.I'd be surprised if someone didn't do some version of it already.

    I've never seen the lever deal on VW reduction boxes but I know the made alpine gear sets for them.
    Last edited by Booger1; 10-03-08 at 09:05 PM.
    Everything should be as simple as possible...But not more so.---Albert Einstein

  10. #10
    Zoom zoom zoom zoom bonk znomit's Avatar
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    Flip flop hub with different sized cogs?

  11. #11
    Senior Member cyqlist's Avatar
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    Quote Originally Posted by kuan View Post
    LOL! That Sturmey Archer would mean three shifters on a bike.
    Like this:

  12. #12
    I live in a bicycle. smovlov's Avatar
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    http://sheldonbrown.org/otb.html

    63 speeds. There is a description 3/4 of the way down.

  13. #13
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    I had the Shram dual drive on a recumbent. If it is anything like a Rohloff, it may have a minimum ratio or it gets overstressed, relative to a tripple up front.

    I used to have this gizmo, it's still out there, where you mounted a 4th ring on the inside of the the tripple. You could pull a stump with it. Not sure whether it would work with modern shifters, but it was fine on friction. It's a mountain tripple thing.

    This isn't the one I had, but it is a similar idea:

    http://www.abundantadventures.com/mt_plus.html

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