I can't find anything on that purple carb, it is however identical to the black, red and gold carb early model with the barrel stop screw.
it has a a main needle but no LSN or idle set screw, am I missing something or the idle set screw is not required.
Also when I close the barrel the engine doesn't turn off, I have to cover the carb with my finger to shut it down.
thanks,
Dan.