I'm syncing my carbs and getting the bike ready for the road.  I noticed this tube that looks like it either should be capped or connected to something.  It's between the carbs.  I have looked at carb parts exploded drawings and many videos but can't "see" it.

Can anyone tell me what it is and more importantly should I leave it open or should I cap it?

Leave it as it is, my bikes are both like that. Not sure the purpose. Maybe overflow for stuck float??

As Abe said, leave it as it is, it is supposed to be bare (at least on a V Star, as these  carbs have multi-able applications)

Great.  Thanks to both.