ORIGINAL: Dr1Driver
There's only one good way to set a ST low end needle.
Place a short piece of fuel tubing on the inlet nipple. With the carb at idle, and the idle needle closed, blow through the tube. Hold the carb throat to your ear while slowly opening the low end needle. When you can JUST hear air blowing through, you're within 1/4 turn either way of the right setting.
Dr.1
This is the best way. It gets you very close and you can adjust from their. Rotating the spray bar has nothing to do with an intial setting. Maybe afterwards but that is not the original question here.