jeffrey......

rich bottom isn't the problem.......the problem is running the MAIN needle too lean, because this needle controls how much fuel get in the carburettor.....

to check the bottom setting, accelerate your engine very slowly up to full throttle and let the engine run at full rpm for 2 seconds, then idle.....if in the next 15~20 seconds the idle stays consistent, it's ok......if the rpm raises, the bottom is lean, if the rpm goes down, then it's rich.....