it's a little hard to see but it's brass

That's an overflow pipe from the float bowl .
You could have a few problems causing it to drip .
Most likely is the needle and seat valve doesn't quite shut off fuel supply to the float bowl .
When the bike is on its sidestand , often it's on quite an angle , which raises the float level
on the left side of the carb . If you see photos of many of our bikes garaged ,
the sidestand sits on a piece of 4x2 timber to minimise this effect .
Try the 4x2 method , if the leak still drips , then a needle & seat replacement is in order .

Currently the bike is sitting level on a bike jack. The carb was just rebuilt. I read something about the tube may have a crack in it. I guess I can remove the carb and check that., thanks

Lots of needle and seats don't completely shut off with the float .
It doesn't effect normal running , but will weep when sitting over time .
What I , and others do,  is turn off the fuel petcock on the tank a couple of hundred yards  before coming to a stop .
That leaves only a small amount of fuel in the float bowl , and with the fuel tap off , it can't refill .
I find with bikes that are only used occasionally , this makes starting easier , as I have reasoned , 
though I may be wrong , that if the float bowl fuel is left for some time , it goes stale , but the fuel in the fuel tank 
seems to keep fresh longer . I'm not in US , so your fuel may not react the same way .
 

great idea......thanks