carb adjustments

Discussion in 'Whizzer Motorized Bicycles' started by bobthefish19, Sep 21, 2013.

  1. bobthefish19

    bobthefish19 New Member

    My wohizzer is not running properly and I think it has to do with my carb adjustment and those screws. I live in south Florida so elevation is not a problem. Can the manual say s 1.5 full turns on both. Can anyone else advise or give me any suggestions

  2. locksmith

    locksmith Member

    what is wrong with it? bogging? no high rpm's?
  3. bobthefish19

    bobthefish19 New Member

    It sounds like it gets high rpms but eventually boggs down and dies out. Sometimes it sounds like it's getting to much gas. It does not stay running the same amount of time every time.
  4. jaguar

    jaguar Well-Known Member

    If it bogs by opening the throttle completely when accelerating then it is too lean.
    If the only time it runs right is when accelerating with throttle wide open then its too rich.
  5. mason_man

    mason_man Active Member

    Your main jet should be #76 or #78. the main jet is the center one, 2 parts, take the small brass screw(jet)off and make sure you can see through it, if not then it's blocked. now take the little jet just in front of this one and carfully blow it with air, and check if you can see the tiny hole that runs through the middle (it gets clogged very easy) if it is clogged clean it with a very fine wire ( like from a wire brush) and blow it until you see light.(yes it's a tiny hole!!)
    Did you finally get the W clip? I got your PM sorry it went to the wrong address you gave me. let me know.

  6. Quenton Guenther

    Quenton Guenther Motored Bikes Sponsor

    Although I doubt it is your carburetor, you are welcome to send carburetor to me and I will check it out, and test and adjust for you [no charge]. All you have to do is pay for return shipping.

    This way you can be sure what your problem actually is.

    Most often the WC-1 carburetors were shipped with 80 main jets, and were too large for a stock motor. The symptom is the motor "bogs" at W.O.T. and will speed up when the throttle is turned back to 3/4 throttle. Unless the main jet is way too large it won't effect the basic operation of the carburetor. Most often the pilot jet effects the operation just above idle, however it can also cause idle issues if completely stopped up.

    Have fun,
    Last edited: Sep 23, 2013
  7. Fabian

    Fabian Well-Known Member

    My current engine (when using the NT carburettor) needed a #77 main jet. The previous engine of identical engine capacity needed a #70 main jet and the engine before that needed a #83 main jet to operate correctly.

    It seems that the average jet size for 98 octane fuel (in my location of Melbourne, Australia) and using 25:1 oil/fuel ratio is around a #76 main jet.
    It always perplexes me that these Chinese 2-stroke bicycle engines have such significantly different fueling requirements from engine to engine. They are terribly inconsistent; sometimes from day to day, which makes a diaphragm carburettor the logical choice, for it's user friendly (screwdriver adjustable) external jetting design; deleting the need to get fuel all over your hands and the garage floor every time you need to adjust the carburettor jetting.

    Life would be so much easier if a diaphragm carburettor could be made to work on a 4-stroke, but small fuel injection systems are already available for small capacity 4-strokes, which is the best solution.