Alright one more update for today. Did a lot of little tinkering with these things and dont know what is actually relevant or not so i'm just going to vomit out a bunch of things I saw.
Removed choke plunger. It was very black so I cleaned it up real good, no change in how fast the slide falls.
Swapped the right (good) side diaphragm and slide to the left carb, still fell just as fast.
Put the carbs back on the bike and started it up, sprayed carb cleaner all over the left side carb but there was no stuttering.
Took the pod filters off and plugged the top hole on noth carbs, Right side slide basically stopped moving while the left side one moved up and down even harder.
Sprayed carb cleaner into both carb intakes, right side caused stuttering while the left side shot the rpms up.
Both carbs have 137.5 main jets with all the other jetting bits being stock as per the manual with the jet needle clip on the 4th space from the top and both mixture screws are turned out 3/4 of a turn.
There is a noticeable difference in the sound from the left exhaust while the bike runs, sort of a lower possibly slightly slower "thumpier" sound.
The bike also wont start unless I have the throttle cranked all the way open, not sure if thats really an issue but I would assume you shouldnt HAVE to do that.