Can anyone give me advise on my ATV

So

HONDA TRX 200. (1991)

I have this COUGHING sound in the idle.

What causes this ?

How do I fix it ?

I know little about CARBS …..

When I took the filter off and looked int he airbox while it COUGHS I see a small puff of gas/airixture or smoke when it coughs

If I turn the idle screw barely to slow it, it coughs more and dies

If I turn it the opposite a little it REALLY starts to idle FAST..

Either direction i turn it, I’m talking an 1/8 of a turn

Here is a VID —
https://vimeo.com/145080774

Any help is appreciated