Here's an easy one

[2GbeemerLUV]

Sorry if this is redundant as I know this is a common misfortune of an airhead ( but I put the "ewe" in noob): puffs of black smoke out of right exhaust when bike leans left or on side stand.

I know this is a recourse of unburned fuel or rich mix (I'm getting equal spark on both sides visually, but left head is working fine where as the right is not responding to air screw adjustments and dies when shorted and allowed to run on its own).

What else does this tell me and what should I be checking first?

[ritetwist]

Have you checked the plugs? I would guess the right one would be fouled,black and carboned up.
Carb cleaning is in order,check float for gas level,is it shutting off?
Could be just a bad or badly fouled plug.
Start with the basics.

[Stagehand]

failure to respond to mix screw adjustments points to a blocked or dysfunctional idle circuit, to my idle, dysfunctional brain circuit.