Actually, on the EVAP it does the same, tho via a valve that opens when you turn the ignition on. I even checked that valve when i was troubleshooting it and it works fine. But before it goes to the valve i think theres another T joint that splits it up so that another hose goes from there to the aux cannister. I looked at it for a long time trying to figure out just how it works but i can't figure it out. Doesn't matter tho.......i was just trying to figure out what i should do with the vent fitting if i decide to $hitcan the EVAP.
By the way, the float bowls themselves of course aren't physically attached to the vent, (as u said why Pat probebly said that) but apparently they vent the bowls thru a passage from where the vent tube attaches to the carbs. i found some other posts here about it and even one where someone talks about the vent hose getting clogged and his carbs overflowed out the back. So when a bike is running rich on both sides that hose should probably be a priority suspect since few other things would cause both sides to foul. It need not be fully blocked in order to run rich w/o overflowing into the airbox i suppose.
