Something I've noticed as I've been pulling carbs apart and cleaning them; the ones that have had the EPA plugs removed almost always show extensive corrosion on the pilot screw springs and washers. Given the orientation of the carbs, moisture is getting in past the screws and corroding the steel parts.
The pilot screw hole measures 0.250" or 6.45mm in diameter.
I've found some silicone plugs which go from 4.7mm to 8.7mm over a 16mm length. Think these would work for capping the pilot jet holes when the carbs are fitted on the bike? Given the length, they ought to be easily removed for tuning.
