Going to die when clutch on gear

[Lian]

Hello.

GasGas 300, 2011.


Problem is:
When i'm on gear, pulling a clutch, let off throttle - idle drops to verly low, i can even stall if not make blip of throttle, but than idle drop again to very low, therefore bike is often stalling or can't get quick throttle responce to make something technical (ex. trials jap-zap or lift front end to place bike in different way).
Some time idle on gear is keeping normal, but if i hold clutch more then 10-15 sec it drops low. When i put N after this, idle still remains too low if i will not add throttle.
In this video i made high idle for purpose (idle screw IN), to show how low idle drops on gear even if it was high on N before.
https://youtu.be/k7FGbWzs2TY

-----------------------------------------------------------------
New piston, clutch basket's walls are straight (have checked in case of basket' wear and not letting discs release).
Motul Transoil 10-30 new.
Have changed 5 idle jets (50...40) and 2 needles N8RG and CCK (all on 1-2 step - lean (1), richer(2) ). And main jet 165-170-172 (but mains not really affects on idle).
NOTHING changed (idle on gear)!!! It remains sooo low.
Air screw of course changed behavior of idle on N, but idle on gear it seems nothing affects.
-----------------------------------------------------------------

As i know, idle low when mixture are too rich, like i'm tightening air screw IN almost to full close - engine is choking (i.e. breathless), so i thought it behave like rich when im clutching and i put leanest of my jets - 40 idle jet and needle max down (leanest), air screw 1,1/2 out. Tried. When open throttle - dun-dun-dun-dun lean mixture (like im out of gas), but Idle on clutch (on gear) remain the same - nothing changed again... so my theory (rich mix) are broken, is it?

Here is small cut of behavior on riding - u can see constant drops of idle on gear-clutch.
https://www.youtube.com/watch?v=s9Phnj020Gs