Re: bad experiences so far :(
first thing i would check would be the throttle slide inside the carb housing. sounds to me like it is not lined up in the notch and nub there fore the needle does not operate properly. Unscrew the top of the carb and remove all parts. verify that they are together properly then put the slide back in make sure you line the nub up on the carb housing to the notch in the slide. take off the air cleaner so you can see inside and make sure the slide goes up and down with turning the throttle.
Ride it like you stole