Can someone tell me what this hose is?

[jryan]

Right below the carbs on right side of RSV, I'm trying to figure out what this hose is for...and what it connects to. I'm sure it's an easy question, I just haven't stumbled across it in the Service Manual. Thanks for the help...JR

[van avery]

On a 1st gen it is the breather for the crankcase. It goes up to the bottom of the air box / air filter area.