Evaporative canistor?

I was told this by the tech, and noticed when picking up my R3R their was a R3T with only (shown by the tech) one hose. the charcoal is not supose to have raw fuel entering the evaporative canistor, the fuel will damade the charcoal.

Had a evaporative canistor replaced on a vehicle because of raw fuel entering it and leaking on the ground. I guess it is different for bikes, as I thought that (no matter how much) raw fuel leaking on the ground was bad for the environment .
 
Thats why stations make a big deal about not squeezing that last little bit into the tank, it runs right down the vapor hose into the charcoal and can fill the canister full of liquid fuel.
I don't understand why a canister wouldn't have a line coming out of it open to the atmosphere, In fact the Standard/Classic R3 service manual shows one from the canister and one from the fuel filler neck. Don't know why a Roadster would be different ... the idea behind it is that as the fuel in the tank evaporates, the pressure and vapor leaves the tank via a hose to the charcoal. Then the charcoal tank has a line open to the air and the charcoal absorbs the vapor while the pressure leaves through the open hose. When the engine is running a vacuum line draws outside air through the charcoal where the fuel vaporizes again and is burned in the engine. The line's opening from the tank is at the highest point inside the fuel tank and is supposed to only draw vapor, but overfilling or tipping will of course let liquid into the line, and it's gotta go somewhere.
Then there is still the overflow drain from around the gas cap, it's function is obvious.
 
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