I ask this because I noticed a small amount of back firing when I did my pair removal yesterday and bluing of the exhaust.

Mods
K&N
D&D slip ons
Pair block off
Carb
45 pilot
Dynojet kit
extra lift hole
5 clip needle with stock spacer
190 fmj 195 rmj
2.5 turns out

Any thoughts? bike runs decent, throttle response is poor when its cold but I figured it was a big V twin thing but maybe someone has some insight? Runs strong when warm, sometimes throttle response downshifting is a little laggy sometimes its perfect.

 

If you do some searching you'll find that your current carb set up is not what most (all) members here, that are very experienced at such things, will recommend against such a set up.
That said, you can pull the enrichment (choke) **** out a bit and see if the popping gets better or worse. That will tell with out a doubt if your lean or rich.