my zilla is had to start with the carb set correctly maybe because it's new not sure though
Adjust needles in this order. Note: All settings vary with climate and elevation.
High Speed Needle: Between 3 1/4 and 3 1/2
Low Speed Needle: Turn Counter Clockwise OUT until FLUSH with the Slide ball- linkage and then Turn Clockwise 1 turn IN for stock setting.
Mid-Range Needle: Turn Clockwise until needle stops then turn OUT Counter Clockwise 3 1/2 turns.
(note: With carburetor slide held open. Turn midrange needle clockwise to close, when you feel it snug, stop immediately. That is the closed position.)