Sprocket size????

Discussion in 'Motorized Bicycle General Discussion' started by Chitty, Jun 5, 2008.

  1. Chitty

    Chitty New Member

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    We have ordered a 80 2 stroke kit for my wife, but have yet to get a bike. She wants something that is easy to get on [low]. The kit says it is for a 26" weel, so if we went with a 24" weel would we need another sproket?
     
  2. Ilikeabikea

    Ilikeabikea Moderator
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    Using a 24" wheel will make the bike slower, unless you go to a smaller sprocket.....................................
     
  3. HoughMade

    HoughMade New Member

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    If you went with a 40 tooth sprocket instead of a "standard" 44, it would compensate. A 24" is about 92% percent of a 26", and a 40 is about 92% of the 44. 40s are pretty widely available.
     
  4. spad4me

    spad4me New Member

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    Re: You man need to go rack mount.

    LOOK at the mounting space needed by the engine..
    Quote We have ordered a 80 2 stroke kit for my wife, but have yet to get a bike. She wants something that is easy to get on [low]. The kit says it is for a 26" unquote .


    Yes, a Happy time framemount chinese 2 stroke engine will fit a 18 (shoehorn needed) to 26 (very easy) MEN'S with a diamond shaped opening in the middle bicycle.
     
  5. spad4me

    spad4me New Member

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    A rack mount friction drive is the only kit that I know of that the rear wheel size does not matter.
    The rear wheel is only a spacer between the drive spindle and the ground. LOL

    A small ish 32 cc subaru rack mount friction drive will last forever and fit everything.
     
  6. Bikeguy Joe

    Bikeguy Joe Godfather of Motorized Bicycles

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    The rear wheel size does matter...a little, a 24" wheel will have a slightly lower overall speed at any given rpm than a 26".
     
  7. cityevader

    cityevader New Member

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    Except for a friction drive, which drives the outside diameter of the wheel at a certain speed (not rpm as a sprocket drive does) which would be friction wheel RPM multiplied by it's circumference. So the tire tread tavels a certain feet per second,not revolutions per second. And since the tread is connected to the ground, it then travels at the same feet per second.
    So rear tire diameter is irrelevant on friction drive.
     
  8. Easy Rider

    Easy Rider Santa Cruz Scooter Works

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    Like Big Joe said: It won't make that much of a diffrence but the up side is she'll have better low end torque.
     
  9. cityevader

    cityevader New Member

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    But the only thing to increase/decrease bike speed on friction drive is to change the drive wheel size, not the driven wheel size.
     
  10. Easy Rider

    Easy Rider Santa Cruz Scooter Works

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    My mistake. I didn't read the whole thread. I thought the discussion was about sprockets. You are correct that on friction drives, the diameter of the spindle determines the speed.
     
  11. Bikeguy Joe

    Bikeguy Joe Godfather of Motorized Bicycles

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    The OP was talking about a frame mount chain drive model.
     
  12. Bikeguy Joe

    Bikeguy Joe Godfather of Motorized Bicycles

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    Anyhow- to the OP- A different sprocket is not required or needed, unless she is going out for a high top speed or loooong cross country cruises, then it will be a help, but still not a requirement.
     
  13. cityevader

    cityevader New Member

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    You're right too! It started out as a sprocket question, and somehow I ping-ponged into friction drive...my fault!

    HoughMade's response says it all.
    But I might suggest using whatever sprocet the kit comes with, so you don't go spending money before you even know what you like. If after engine break-in, you want more torque and willing to tade off top speed, then go bigger sprocket. If torque takes a back seat to top speed, get a smaller sprocket. But base it on what like/want from experience.
     
  14. sisdavid

    sisdavid New Member

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    Shouldn't be a problem with the 24" wheels. Just going to be slower and a little more trque. If a person is larger this set up is ideal.
     

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