Fuel vapor recovery system

[dxhall]

I am struggling to understand how the charcoal canister system on the CalVin works.

There’s a larger hose that goes from the tank to the charcoal canister.  This hose has a one way valve in it - it allows air to pass from the canister into the tank, but not the other way.

There’s a smaller hose that goes from the canister to the intake manifolds.

And finally there’s another hose on the other end of the canister, which I assume is a drain.  This hose is open to the atmosphere.

I don't see how fuel vapor can get past the one way valve to the charcoal canister.  What am I missing?

[Mayor_of_BBQ]

There’s a larger hose that goes from the tank to the charcoal canister.  This hose has a one way valve in it - it allows air to pass from the canister into the tank, but not the other way.

Shouldnt it be the other way around?

[dxhall]

Here’s how it is supposed to work:

The main purpose of the charcoal filter and the charcoal canister is to absorb excess gas fumes from the fuel system and the gas tank while the engine is off. The filter inside of the canister acts like a sponge and absorbs all of the excess gas fumes. Once the engine is restarted, the excess gas vapors return to the fuel system and into the combustion chamber.

On this bike a prior owner disconnected the line from the canister to the intake manifolds.  Would it make sense to  reverse the one way valve when the manifold line is disconnected?  I wonder if this is what happened.