Clean and polish the float valve seats with a cotton stick with autosol attached to a drill. Don't use to much pressure on the drill other wise the stick will bend.esvir said:
Then check the float valves and the little pointy rubber bit and make sure that they're clean and don't have indentations on them and if they do, replace them. Not sure how they cost at Honda but I got some spare ones.
A little test I used to check whether they were working was to flip the carbs upside down, assemble the floats, valves and have them in the carbs but have the bowls off put some fuel down the fuel hose and apply light air pressure on the hose to replicate the weight of the fuel in the tank. If fuel comes out from the seats and where the valves are then you know that it is leaking there.