[Aussiecrf230]

Hi again,

What idle jet is in the bike at the moment?
Have you tried adjusting the fuel screw?

If the engine speeds up when you pull the choke on then the mixture must be lean.
So either
Air leak
Blocked idle jet or passageways
Wrong idle jet
Improperly adjusted fuel screw for bike.

A lean engine will jump around and have to be set at a fast idle so it can draw fuel from first part of needle.

If no obvious air leak try adjusting fuel screw to get fastest idling and see if you can adjust your idle speed down with the idle speed screw.

[Leardriver]

The passage above the pilot gets plugged. It is possible that the other carbs that you tried had been sitting and were also plugged.

With the pilot jet out, spray carb cleaner up into the hole, scratch up in the passage with a dental pick, some compressed air, and when you have air coming into the inside of the carb bell, you will idle.