One of the things with side stands is that carb floats are more likely to stick a bit. The float bowls get a little over full and when you lift the bike there's some spillage. Turning off the engine and waiting a few seconds before dropping the bike onto the stand from being upright might help as this makes sure that the fuel tap is closed. Make sure that the fuel tap isn't set to Prime as well.
There are lots of other possibilities though. One is that the spigot is the air filter drain, in which case it's more likely to be oil than gas. This could be a result of an engine that's perhaps due for a rebore and new rings
There is supposed to be a tube attached to the spigot you mention, whichever one it is. It's to make sure that any spillage is routed down to the floor below the engine. You don't want drops of fuel accidentally hitting somehing hot, and you don't want it hitting anything that should be lubricated, as it washes the oil or grease away. If it's drops of oil (often mixed with a little gas), it makes a mess.
Last edited by williamr; 12-18-2012 at 04:58 AM.