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,