That just means your carb is out of adjustment.
When you tune you first tune the high speed needle to get the top end you want. A bit rich is always better.
Then you tune the low end to get the acceleration you want from idle.
Then retune the idle setting. When you lean out the low speed needle it makes the idle higher if you have to lean it much. So you then have to turn the idle screw counter clockwise to lower the idle. Sometimes motors are set to rich on the low speed, then compensated with an idle screw that is holding the carb open to far to keep from stalling. A sign of this is after a high speed run when you let off the engine keeps revving a bit.
If you're creeping off idle like that and giving it a good bunch of throttle, just screw the high speed needle in clockwise an 1/8 of a turn at a time. Glad you got it working.