i just got a gokart up north and it has a 5hp briggs flat head, well being the guy i am i knocked the head off and cut down the eye brows, pulled out the governor, and am running no head gasket. well now no matter what i do with the air screw, i cannot get it to run right. it will idle very nicely but when i hit the throttle it bogs and dies. im into quads and stuff and am not a stranger to carbs my question is am i suppose to rejett, 

or is there another issue?