firstly the carb must be flooding,is there any fuel coming from the over flow pipes on the side of the carb? and are they clear?you havent blocked them off or raised them up above the float bowl level have you !the float needle 'seat' sometimes has an o ring on it on and the seat is detachable from the carb body if this is so then undo the small screw that holds it in place and pull the needle seat out and replace the oring,the float has a specific height from the gasket surface without the gasket fitted when you turn the carb upside down,i will find out what it is and tell you.also you need to check the neeedle and seat are in good condition with no rings worn into them look at them with a magnifieng glass to see as they are very small ,debris in the fuel will also cause flooding as the needle cannot seat in the needle seat properly and stem the fuel flow.i know the choke is ion the carb and it wont cause the flooding your describing even if it was stuck on which i doubt it is.ill find out the float height tomorrow and let you know if you want ?
adam bike doctor, February 2010