Leaking fuel from a carb is usually because a carb float valve is stuck open. I would replace the float valves, a good idea anyways if they are the originals from 1981, and check the float levels. Make sure the floats are not damaged so fuel is inside them. Also check the air filter, to make sure it is not clogged. Sometimes old spark plugs or a bad battery will make the engine seem like it is getting too much fuel, because not all of the fuel is getting burned.
If this does not work, you may have to do more cleaning for the pilot mixture screws and the passages where these screws go- if the pilot mixture circuit is clogged, the carb runs off the choke passages instead and runs way too rich (too much fuel).
I would also try adding Sea Foam to the gas tank- sometimes it will clean up a dirty fuel system the easy way:
http://www.webbikeworld.com/sea-foam
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