For the first time in several years of owning my ducati, the tank gasped for air when i opened the tank to fill it up. I didnt do any work recently to it, and i was aware of pinching breather hoses causing this issue. So i immediately checked this, no problem. Now i decided to disconnect the hose from the canister and disconnect the hose that leads to the throttle bodies and plug it, avoiding any vacuum leak at the TB.
So my confusion is this: according to the shop manual, the breather hose should have vacuum from the canister (arrows in the diagram lndicating air flowing out of the tank to the canister). my breather hose is creating vacuum towards the tank(which to me makes sense since it allows the tank to breath and not stop the flow of the gas in the tank). which is correct? if air is supposed to leave the tank thru the breather, what allows the gas in the tank to flow?
The factory system allows movement of air in either direction depending on the pressure/vacuum in the tank.
The removal of the canister does the same thing except the fuel vapor now vents to atmosphere instead of the charcoal canister.