Bike only runs on hot start, dies with throttle

Darwin and Wrench are right on with their comments. The easiest way to find an air leak is with a spray can of carb cleaner. Spray it around the outside of the carb and if your idle speeds up you found the leak. The idle jet screw is only good for the first 25% of throttle opening. The high speed main jet is for 75% to wide open throttle. The tapered needle on the slide plate is for the 50% in between these. Resetting that clip on the needle to factory was the right thing to do, but you will see NO effect from this at idle.

Spray a small mist of carb cleaner into the throat of the carb. If the RPMs increase it wants more fuel obviously. If it bogs down then it's too rich and doesn't want any more. I think you understand carb tuning more than you give yourself credit for.