Mikuni jetting and tuning issue

I have a '73 850 commando with a just installed brand new single VM34 carb. Initial specs were: Main-240, Needle Jet-159 P0, Needle-6DH3, Air Jet-2.0, Pilot Jet-40, Slide-3.0, Air Screw-2 1/2 turns out. Bike started ok with these parts. Used choke to start. Had to leave choke on for at least 10-15 seconds or else the engine would die. Adjusting air screw would not significantly increase RPM's. After warm up rode bike but never got past 1/4 throttle. Engine bogged down and died unless I backed off on throttle. Pulled clutch shut off engine and inspected plugs. Severely carbon fouled. Went to #35 pilot jet. Same thing. #30 P.J. same. #25 same. Any throttle past 1/4 produced bogging and engine dying. Mixture obviously too rich. Tried a 3 !/2 slide. No difference. Even though the Needle jet and Needle don't become a factor until after 1/4 throttle I tried a 159 O/0 jet with needle clip 2 notches down from top anyway just to see. Nothing or any combination of jetting or settings has gotten a smooth transition past 1/4 to 1/2 throttle. Engine always bogs and dies. In addition plugs are always black. I also noticed that the pipes turned blue after multiple starts trying to figure this out. From what I've read this a sign of a hot running engine most likely caused by a LEAN mixture. Between carbon fouled plugs (RICH) to blued pipes (LEAN) to multiple jetting and setting combos I'm at loss. Any help in figuring this out would be hugely appreciated.
Current parts are Main-240, Needle jet-159 O/0, Needle-6DH3 (2 down from top), Air Jet-1.5, Pilot Jet-32.5, Slide-3.0.

What air cleaner are you using?

Go back to the P-0 needle jet and 340 pilot. Use the 2.0 air jet.
I am guessing that there is something wrong with choke valve. Pull it out and carefully inspect. It may need replacing altogether. A new one is about $15.
Your original jetting is very good. The only other supply of fuel is the choke.
Check float level.
Remove the air cleaner and see what happens. It would have to be REALLY clogged to produce the results you're talking about.

I meant the #40 pilot.

Check the enrichener plunger seal, and adjustment, that it is seating properly.

Also check for foreign material in the air passage from the air horn to main well.