Are you sure it's gas and not condensation? Does it leak after riding for awhile?
You might have to use the adjustment screw to get rid of it. If you are sucking air in from a leak and tuning with the screw to make up for it, I guess that would do it.
Oddly I have one bike that does drip out the exhaust pipe and one that does not....no idea
how to stop the one from making a mess so I put plastic under the leaky one.....usually not more than a few drops over the course of a day or two sitting but still enough to have marked up the plywood floor in my shed before I started using plastic.
Sometimes the float will not shut off incoming fuel after a ride. Make it a habit to switch fuel valve off when done riding even for a short ride. If you switch fuel valve off, there could still be a little fuel to leak out, but not much if any. Another problem that can cause this is the white plastic float donut gets filled with some fuel because it may have a hole in it. If your donut gets some gas in it, it will not float well causing excess fuel to run into your motor and out the exhaust, intake and other places as well. Oil drip or seap from various places such as head, cylinder base, exhaust ect., is normal. Keep your engine and bike super clean. That way if there is a problem, you will know right away because you will see it when cleaning. A dirty bike and motor is a bike and motor getting ready to fail.. Keep your bike and motor clean !!! Enjoy the ride....