lost top speed

Discussion in 'Motorized Bicycle General Discussion' started by 4wdingman, Oct 4, 2008.

  1. 4wdingman

    4wdingman New Member

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    Hi
    I have lost top speed ever since I have got a new carby. It very strong and takes off great but it seems like it doesn't hit top speed. Once it hits top speed it feels like the clutch is on. The clutch is not covering the air hole and the trottle does not cover it too.
    So can you thing of a reason why it has lost top speed???
     
  2. BlueCollarBike

    BlueCollarBike New Member

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    Check to see if the screen in the Tank petcock valve is dirty.


    cheers:)

    Bob
     
  3. tyrslider

    tyrslider New Member

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    If your float level is too low it could cause this. When you stop your using less gas so you would have enough to start out good, but you could be,in affect running out of gas at higher rpms.
     
  4. Bikeguy Joe

    Bikeguy Joe Godfather of Motorized Bicycles

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    Check your plug first....see what color it is. Shouldn't be white or light grey. Should be tan to chocolate brown or a slightly oily black. If you are running too lean it will seem weak and get hot quick, too rich and it will have a good pull, but when you hit cruise or WOT it could "4 cycle".

    Now, what do you mean "The clutch is not covering the air hole and the throttle does not cover it too."?
     
  5. 4wdingman

    4wdingman New Member

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    sorry i meant the choke any way i will check my plug and check the float
     
  6. velardejose

    velardejose New Member

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    Hi
    My mb has great start too (clean sounding engine)
    But when sustaining mid rpms kind of 4cycles
    And when flooring it pulls slow
    Mb has a 'vibration' speed limiter...
    Plug is dark brown
    Should I lean the mixture?
    Thanks in advance
     
  7. Saddletramp1200

    Saddletramp1200 Custom MB Buiilder

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    Jose, Check your carb for torque against the manifold. They come loose and make an air leak sometimes. No we need more info like mix ratio, plug type, ect.
     
  8. velardejose

    velardejose New Member

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    Hi
    I sealed the carb-intake tube joint with grey silicon
    Mix is 30:1
    Plug is ngk b6hs
    Needle clip is in the second notch from top
    Tire press is 40 psi (jk)
    Thanks in advance
     
  9. 4wdingman

    4wdingman New Member

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    thanks everyone
    I switched the jet and the float leveler from my old carby to my new one and it works great i can get top speed...


    thanks everyone
     

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