A new shift concept for the engineers....

Discussion in 'Motorized Bicycle General Discussion' started by ferball, Jul 26, 2010.

  1. corgi1

    corgi1 New Member

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    That would keep the slack out of the top chain when starting
     
  2. bairdco

    bairdco a guy who makes cool bikes

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    since we're mostly talking about things that won't work, how about a multi-piece adjustable sprocket?

    it starts out as a 32, then you screw in a bolt on each piece, and it expands outward? :)
     
  3. Kevlarr

    Kevlarr New Member

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    What about split sprockets like go-karts use?

    Change your ratio without removing the wheel.

    [​IMG]

    I already have my chain set up to use either a 36 or 40 sprocket just by removing 4 links.
     
  4. Allen_Wrench

    Allen_Wrench Resident Mad Scientist

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    I'm still working on my previous idea of a left-hand cassette that slides in and out on splines on the rear hub, with a stationary tensioner lined up with the engine. The design of the tensioner will be everything because it will guide the chain onto the other drive sprocket as gear is changed and as the former sprocket is slid out from beneath it. The rear wheel, as stated before, will need to be pretty flat on that side - but so are all such rear wheels on bicycles with multi-speed cassettes. I believe this is not only do-able but it can be made sturdier than an internally geared hub, if a bit bulky as a result.
    I've actually gotten serious enough to put pencil to paper and sketch a bit. Who nows how long before/if I come up with something workable. But it may still be cost prohibitive enough to make that we may as well not bother. Too early to know, but time will tell.
     
    #144 Allen_Wrench, Aug 15, 2010
    Last edited: Aug 15, 2010
  5. bairdco

    bairdco a guy who makes cool bikes

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    my idea is a joke. you'd end up with an elliptical sprocket.
     
  6. Allen_Wrench

    Allen_Wrench Resident Mad Scientist

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    Couldn't we just engineer a Nu-Vinci hub to work on the left side?
     
  7. curtisfox

    curtisfox Well-Known Member

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    Check out MB pictures page 5 Greatings from Germany Harry has one that apears to be driven from the left
     
  8. Goat Herder

    Goat Herder Gutter Rider

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    I don't see nottalaff http://motorbicycling.com/f15/greetings-germany-all-mobi-fans-pictures-16699.html


    Bio pace sprocket for the China yeah that would rock(^)rotfl

    I am still scouring the net for hubs to no avail. The guy that makes a left side drive internally geared hub, is gonna be rich I tell ya filthy rich.

    The N.V. can be reversed from what I have read. There is a major catch. Have to have new parts custom machined to get a viable left hand free wheel on the left side. The hubs design needs that free wheel sprocket. Or it will drag like mad the balls inside don't ever totally disengage.

    One has to totally disassemble the hub and move stuff around as well.

    Also have to consider the N.V. has a limited duty cycle at some point it has to cool down.

    That said I think it is feasible.
     
    #148 Goat Herder, Aug 15, 2010
    Last edited: Aug 15, 2010
  9. curtisfox

    curtisfox Well-Known Member

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    Staton inc has left hand free wheel hubs
     
  10. scotto-

    scotto- Custom 4-Stroke Bike Builder

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    And to think, all I want is right now is a freewheelin', left-hand drive 3-speed internal hub with a disc brake...not a coaster brake. Am I askin' fer too much???

    You betcha!!! One day perhaps...:-||
     
  11. Kevlarr

    Kevlarr New Member

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    We just need somebody to come up with a small 3 speed (with neutral) actual transmission that basically bolts onto the back of the engine and runs directly off the drive sprocket. :D
     
  12. Goat Herder

    Goat Herder Gutter Rider

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    Why can't we have it in the wheel. Then its truly universal everyone can have it then. Life would be good:D
     
  13. ferball

    ferball New Member

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    I thought the stock sprockets came elliptical from the factor....
     
  14. curtisfox

    curtisfox Well-Known Member

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    I thought that Staton had the hub with left hand thread on the left so it would be the opeset? I will look again
     
  15. Goat Herder

    Goat Herder Gutter Rider

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    They do and its not gonna fit a N.V. hub
     
  16. Goat Herder

    Goat Herder Gutter Rider

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    They do very slightly prolly helps shifting better.

    Remember the old Bio pace sprockets? They faded out rather quickly. Turned out the folks using the normal sprockets were winning all the races.
     
    #156 Goat Herder, Aug 15, 2010
    Last edited: Aug 15, 2010
  17. scotto-

    scotto- Custom 4-Stroke Bike Builder

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    Yes, it's that little thing called "spinning", especially at a higher cadence that wins the races. You can't spin properly when your biopacing, no matter what. Round rings rule, that's a fact.
     
  18. gareth5000

    gareth5000 New Member

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    I found another way round this problem. Drive the front sprocket and use the gears you've already got.
    I've got a shimano 4 spd auto rear hub to try as soon as I get it laced up. I think auto would be cool.
     

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  19. bowljoman

    bowljoman New Member

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    For those that missed it above, sturmey archer makes a three speed fixed gear you can drive on the left side. It does not free wheel in and of itself. It has splines for fixed sprocket AND threads for bmx freewheel. It is made for fixed gear riders who want a three speed like the awc. Search for the SA s3x 3 speed. released this year. Comes is four colors I think.
     
  20. bowljoman

    bowljoman New Member

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    If you can get by without the neutral, the shimano tricycle transmission rules. Neutral is not needed. either manual or auto clutches work with the trike shifter. The trike shifter can run all day and is only warm to the touch.
     

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