i would try lubing the cable too and make sure its not hung up on something. i had a twist throttle put on and the dickfaces that did it ghetto-rigged a cable with a splice in it. a few months later, the cable kept popping out of the top of the splice when i would turn the bars to the left, causing it to rev. it also got stuck open while i was riding trails. i was only in first gear and it wasnt really bad, just kinda like an unwanted/unexpected cruise control. i put heatshrink tubing over the splice so it wont pop out anymore, but i got an original thumb throttle coming in tomorrow, so i wont have the twist anymore. good luck. if the carb is such a hassle and pain in the ass, you could just give it to me. i think thats about all i need for my motor now except maybe for a stroker crank!