blocked off pipe?

[kev25v6]

i was cleaning my new bike today and noticed that the end of a pipe underneath the bike ws capped off, it looks like a drain or overflow pipe of sorts coming from  just below the tank. when i took it off a bit of water came out of it. should this be capped off or left open? could it be from the tank filler neck for excess water to run out of?

[Red01]

The one with a cap should be the airbox drain. It should stay capped, but opened once in a while to drain any moisture, fuel or oil that will collect in the airbox. You want to keep it plugged so the carbs don't suck up dirty air off the road since this tube drains the box from between the carbs and air filter.