KZ440 wont idle

My 1980 KZ440 was sitting for 2 years and I can't get it running

In short it cranks but wont start without a running start down the driveway and pop the clutch. Once running it will kill when adjusting idle down below 2000rpm sometimes right away other times up to a minute or so. A few times it has started back up most times not without a running start. all whether engine is hot or cold.

I started with new battery and cleaned carbs(not very thorough at first but that always got going in the past)
Replaced left carb because I broke choke link
Replaced ignition coil, spark plug, caps, point and condenser,
Checked for faulty ground, fuse tubes, ignition and stop switch, valve clearance, compression test regulator rectifier, timing
Carbs were soaked and compressed air through all the passages, no holes in diaphragm sealed and move freely, replaced jets, float bowls have fuel and level is fine, bench synced carbs, fuel mixture screw set 2.5 turns out also tried more or less half turn at a time, sprayed carb cleaner around to check for vacuum leaks
Replaced cylinder head which came with valves and rocker
Fresh gas, oil, filter

If those are CV carbs there should be 2 small ports on the intake side of the throttle valve. Those need to be clear for it to run. Look up the diagram and youll see how they work. IIRC, you need to plug one opening while spraying cleaner through because its a 3 way port.

This is similar to how it works, one of the 2 ports feeds fuel all the time and the other is metered by the screw. Remove the plug covering the screw if there is one so you can spray cleaner there, count the screw turns first. You need to alternate blocking the air screw port, slow jet port and the 3rd small port (which is probably the clogged one).

I would bet on two problems.
As Kidkawi points out, the low speed circuit in one or both carbs is clogged, or ther is an air leak that spraying carb cleaner will not detect. If the carb holders are stiff and have surface cracks, it is likely they are leaking. Could easily be both problems.

The starter problem sounds like something is preventing full battery power from getting to the starter and ignition system. Every bit of power that a healthy battery can produce is needed to start the engine. If there are dirty, corroded or loose connections in the starter or ignition circuits, even the best battery will not be able to start the thing. I would first test the battery. Put the meter leads on the battery terminals. Turn the key on and note the voltage. Press the stater button while watching the voltage. Check the manual for the exact number, but if it drops below 11 or so, the battery may be at fault. Yes, a new battery can be bad. Next, I would perform the same sort of test at the coil to see how much power is getting there. It should be very, very close to the reading you got directly from the battery. If those check out fine, I would next test voltage coming into the igniter.
Do you have a factory service manual? It describes how to do this sort of diagnostic testing and has the exact measurements for your specific model.

How does it run with your petcock on PRI?
Wondering if your vacuum petcock needs a high vacuum to flow fuel.
Also, with the fuel cap open?
Clogged vent check.

I wonder how it went?

One other thing to check is that the points gap is correct. On the 1980 (only 440 with points) the gap should be .15mm, and if it's not large enough then the spark will not be sufficient for low-speed running. Looks exactly like clogged pilot jets, so that can be a very misleading problem. If the gap is incorrect, you will need to set them correctly and then adjust the timing with a timing light. Be sure to check the timing with the engine running at idle speed (below 1500RPM). If the carbs are clean enough, then there shouldn't be any issues attaining that with the points gap set correctly, assuming the other ignition components are fine.