Its a banshee thing. If you cut down the return springs, make sure you stretch the remnants of the spring to as tall as it was previously, before the cut. Also, doing this will leave you with a sharp end on the spring. You want to make sure you manipulate that sharp end with a pair of pliers so the spring wont chew up metal, which will end up in your slide bore, or worse, your motor.
This helps, did it to mine a long time ago. Just know you run a risk of the throttle sticking wide open. You will want to sync the carbs for sure after doing this.