There is a rubber 'seal' on the bottom of the brass plunger. They get hard over time and leak gas into the airstream when the engine is running.
Hunter
Are you saying there is a rubber disk
at the bottom of that orifice that the plunger goes in? I didn't see one in there but will look again. Will call dealer to see if I can get new disks in there. I can also try your experiment of running the bike, if I can get it running with the choke cables disconnected. Thanks, Bob