Iame x30 125 loading up after reving it

Hi everyone, I am new to the group. I need some advise on my dirt kart. X30 125. When I have kart on stand and rev it up and release throttle it drops some revs but then loads up on it’s own. I have changed complete carb kit and still no success.

First of all… an X30 on dirt sounds awesome!

Where do you have your H/L needles set? Have you checked the pop-off pressure?

2cycle karts usually aren’t great at idling as they are revving to 16k on the track, which is where you want it to perform and survive.