Ideal rear sprocket size? 44? 36?...

Discussion in 'Hubs, Gearboxes, Sprockets and Chains' started by Nehmo, Aug 4, 2017.

  1. Nehmo

    Nehmo Member

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    Assuming
    a 49cc 4-stroke engine
    26" wheels
    Mostly flat terrain
    Not a racer, just practical getting around

    What's the best size for the rear sprocket? Most kits come with a 44 tooth one, but most CNC ones that mount by clamping the hub are 36t, it seems.
    I don't like the rag connection, and I want to replace it with one of the more accurate clamp-on-hub type. But I need to decide on the tooth number before I order.
     
  2. Greg58

    Greg58 Well-Known Member

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    I run a 44 with my 48cc 2-stroke, I have tried a 41 and didn't like it. Unless you are willing to do a good bit of peddling I'd go with the 44.
     
  3. Nashville Kat

    Nashville Kat Active Member

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    I have a 39 on my 48cc build- Been wanting to change it to 36, just don't have the time. You get better speed and less vibrations, and it handles flat terrain fine. Plus, it's easier to eliminate the chain tensioner then, the chain has more frame clearance the smaller the sprocket
     
  4. MotorBicycleRacing

    MotorBicycleRacing Active Member

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    4-stroke engine
     
  5. MotorBicycleRacing

    MotorBicycleRacing Active Member

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    You are Assuming that we know what transmission you have on your Hausheng.
    Can't give you an answer without knowing that ratio.
    Ignore the advice for 2 stroke motors above.
    You probably need to go bigger than 44 but definitely no smaller.
     
  6. Nehmo

    Nehmo Member

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    The engine I have didn't come with much documentation, and I don't know what kind of transmission I have. How do you tell? 20170805_232642.jpg
     
  7. Greg58

    Greg58 Well-Known Member

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    From the picture you probably have rode it so how good does it work now? If you need more top speed go smaller, more low end go bigger. A persons size makes a difference also.
     
  8. Nehmo

    Nehmo Member

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    Actually,
    I haven't even put the oil in this one yet. I just finished putting it together, and I still need some finishing touches, like a gas cap.
    I was looking for opinions from people who already had experience with a similar setup.
    BTW, what kind of gas cap works? It's a 3cm hole with a 4.5cm OD for the filler tube.
     

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