The engine tends to stutter

[kabl]

Hi, I was doing a stage1 upgrade on my gokart and I have a problem seen in this video: https://drive.google.com/file/d/13v-RwPzP9oGjb04vQnMt0b_qKiwLGYGe/view?usp=sharing The engine tends to stutter when quickly adding throttle from low rpm. it's a honda gx200 clone engine and I have replaced main jet for the 0.037 diameter jet including the emulsion tube, air filter and exhaust. I also replaced the low rpm jet with the one that comes with all those jets. I feel like the engine is low on gas for how much air it has at one time. I have searched the internet and tried fiddling with the screw on the side of the carburetor that adjusts the gas/air mixture ratio, but it has no effect. Do you know what it could be ?

 

[Denny]

Yes, put it back to stock and then leave it alone. It will be as reliable as an anvil then.

 

[Master Hack]

Stumpling when ya dump some skinny pedal usualy is due to a momenary lean condition. I'd tell ya to fix yer accelerator pump, but ya ain't got one.
Someone smarter than me can tell ya how to fix it.

 

[Darren]

If all the fuel delivery to the carb is good, it's usually down to the gaskets and insulator.
Jetting a standard carb for a basic upgrade isn't always required. Take the plug out, it should be a nice tan colour around the tip, whiteish and it's running lean, black and it's running rich.