2005 yamaha 90, what does hose do / for?

[kodibass]

Working on a friends 05 Yam, 90 hp 2 stroke, what is the hose on the side of the exhaust by-pass do / for. not the water discharge (pee-tube hose at the bottom but the one on the by-pass covers side, his is ran through the front & out of the lower cowl pan and is just hanging attached to nothing? thanks kodi

 

[racerone]

Likely for a water pressure gauge.----Other than that wild guess some pictures of the set up.-----One where hose comes out of the motor.------Or the speedometer hose.----Post pictures.