I have a 2000 HD Springer with a Mikuni carburetor, but which is stamped on the top with the Screaming Eagle logo. Today, after shutting it off, I smelled gas, looked underneath the bike and saw a puddle of gas. I then saw gas dripping out of the plastic hose that comes out of the carburetor. I know that the purpose of the hose is to expel excess gas, but to have a continual drip does not appear normal. Is this a sign that the float is not seating right and not shutting off the flow?

 

You are probably correct. Or it could be the float is waterlogged ( I don't think this happens anymore) or somehow the needle adjustment is out.
I just had this problem on an older machine , removed the bowl and float and took a picture up inside the float seat, there was a tiny sliver of rubber stuck there. Removed it and back on the road.

 

Just an FYI, that piece of rubber is your fuel line deteriorating inside. Been there done that.

 

OP, your float is stuck and your vacuum operated petcock isn’t closing

 

Forgot to mention...my bike has a manual petcock, which I always turn to the off position. Perhaps as suggested, it still may not be closing altogether. By the way, any idea why a Mikuni carburetor would have the Screaming Eagle emblem? Were they associated in its production?

 

They were available thru HD Screamin' Eagle. Part# 29641-99