From: dazco
According to greybeard and to what i experienced the problem was probably caused by fuel in the cannisters from filling the tank too much and it overflows. I DID in fact sit on the bike while re-fueling for the first time ever in order to get more fuel into it. the fix for me was to pull the hose off the T fitting on the float bowl vent tube between the carbs. I ran it like that for 70 miles and then it began to hesitate and cut out and run lean. At that point i put the hose back on, and since then 130 miles later it's still running perfect with the plugs looking just right.
Pulling the hose did 2 things....vented the float bowls which were probably not being vented enough due to the cannister being full and thereby flooding the float bowls, and it allowed the bike to purge the excess fuel from the cannister more quickly (70 miles of riding) probably into the atmosphere. The cannister seems to have no way to empty it, but if you remove it i think you could simply by tipping it.
