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Wheels and Axle?

  1. Oct 21, 2009 #1
    I've got two 14 inch wheels and now I need to attach them so that they rotate on one axle. I also need to put a free hub so that when I stop peddling the wheels keep rotating.

    How would I do this. I really need to know even if it's a stupid question.
     
  2. jcsd
  3. Oct 21, 2009 #2
    I dont really get what you are saying. Are those two wheels on the axle driven by pedalling? What is it you are making?

    If you are usign a chain sprocket design to drive the axle, you can just ratchet the pedals.(means you cant go backwards though)

    You could also use an overrunning clutch system if you are using shafts.
     
  4. Oct 21, 2009 #3
    Well, I'm sort of tying to make something like a bicycle but instead of one back wheel, it's two wheels attached to an axle. I know that's pretty much a tricycle but I think that they have pedals at the front wheel. Instead I'm trying to make something like it except the pedals control the back like a bicycle.

    I'm just doing this for fun. I wanted to do this from scratch but I guess it helps telling you what I'm doing. So if you understood what I meant can you help me?
     
  5. Oct 21, 2009 #4
    Then its very easy to do. Just use the existing chain sprocket system, it'll already have a ratchet on it.

    It'll work exactly the same way as a bicycle on with 3 wheels. :D


    I can see the steering and handling being... interesting on it.
     
    Last edited: Oct 21, 2009
  6. Oct 21, 2009 #5
    I'm sorry I'm sort of an idiot.

    I have two wheels but nothing else. I'm guessing I need two hubs, some metal rod I can call an axle and a chain sprocket system. Do I buy the chain sprocket system or what? It's just that you said use the existing chain sprocket system that confused me, because again I only have two wheels.
     
  7. Oct 21, 2009 #6
    By the way,

    If it helps I just got into this today when I found two wheels that I bought but never used. Before today I had no idea what a hub, racket, or a chain sprocket system. I just googled as i went. So go easy on me :shy:
     
  8. Oct 21, 2009 #7
    I just meant the same type of system. Of driving sprocket attachec to the wheels and wheel gear cluser attached to the axle.

    You'll probably have to buy new sprockets to build a rear cluser that fits the axle. Or you could try to jury rig the existing cluster to fit.

    A third option is to use the existing gear cluster from the bike, and mount them somewhere convenient. Have them rotate a shaft with a second sprocket on it and run this to the rear axle with a 1:1 ratio. This means you only need to find 1 sprocket to fit the new axle, but it adds complxity (and therefore unreliability).


    Ahh a layperson :D, in that case if there is anything I gloss over, or you don't understand or whatever just let me know and i'll try to explain it better.

    Please note I am a dreadful teacher, so you'll have to bear with me.
     
    Last edited: Oct 21, 2009
  9. Oct 24, 2009 #8
    I've decided that instead i'm going to make one wheel in the back and two wheels in the front. I think it'll make it simpler. By the way, just to let you know it's not going to be ridden like a bicycle.

    I just want to know if it's a good idea to steer with two wheels like a car with one wheel in the back.
     
  10. Oct 24, 2009 #9
    It's definately better to steer with 2 wheels at the front, it gives cornering stability.

    Normally in faster turns you lean into the turn with 1 wheel, which obviosly you can't do an a tricycle.

    Also 2 driven wheels from 1 solid axle had the effect of not allowing the wheels to turn at their own rate when going torund a corner. This means you'll get scuffing of the tyres.


    2 steered wheels presents fewer handling problems than 2 driven.
     
  11. Oct 25, 2009 #10

    Danger

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    Try Googling 'pedicab'. Wiki has a starter article, but you'll need to search elsewhere for design specs.
     
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