I had to adjust mine leaner than the factory set low needle range allowed. Thsi finally got rid of the hesitation, but I had about 4 or 5 hours on it before I could get it to idle for an extended period and still transition to WOT smoothly.

Don't be afraid to do this, but make small adjustments. To adjust it, just loosen the set screw on the ring around the low needle and turn it in (or out to richen) 1/8th. tighten the set screw and see what it does. Repeat as necessary.

On a side note, I converted mine to needle on the carb after crashing my Twist and breaking off the remote needle bracket. Only thing is now the fuel nipple position is terrible.

Duke