KZ305 csr low rpm sputtering

Okay guys, I know how to work on this bike and I'm at my wits end. I have:

-Installed 2 new 5 ohm Dynatek ignition coils. The spark is excellent.

-Cleaned the carburetor and all passages. Every little hole.

-Inspected diaphragms for tears or holes. They have none.

-Adjusted the valves to factory spec.

-Synchronized the carburetors with a Morgan Carbtune

-Set the pilot screws to the service manual recommended 2 1/4 turns out. I tried adjusting them after while the bike was running, it made no difference whatsoever so I put them back to 2 1/4.

-I've got a brand new battery

-Fresh fuel

-The spark plugs are a beautiful tan color

-Checked fuel levels in float bowl, they are in spec.

It was running pretty good but not perfect. Then it slowly got worse and worse until it's pretty much unrideable. There's no power at low rpms and then it kicks in hard when it gets spun up. It idles very good.

Things that concern me:

-They no longer make the rubber jet plugs for my carburetor. They will go in okay but I have in the past found them lying in the float bowl from vibrating out. They do not make replacement plugs for this bike anymore, aftermarket or otherwise. I've checked Partzilla, no NOS. However, the symptoms associated with these plugs coming out are high RPM problems, which I do not have.

-When I synced the carbs I noticed where I plugged the fittings in to the little vacuum ports in the carb that there was fuel in them when I unplugged them after finishing the sync.

I synced the carbs and then after the bike started running badly a few days later, I checked the sync again and they were off after just 2 days of riding. Re-synced and it's not any better. WTF is wrong with this thing? I have had the carbs off SIX TIMES now and I don't want to take them off again.

Can anyone suggest something? The problem developed over the last 2 days since I got it running.

Adjusted the pilot screws with the engine running at normal temperature and there was no difference. That suggests that the pilot systems are still clogged, the tips of the pilot screws are broken or mangled, or that the orings (if originally equipped with them) are badly torn or missing.
This is assuming that the adjustments were attempted with the engine at proper idle rpm.