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Well, the California bikes have vapor canisters (charcoal?) so none of those nasty gas fumes pollute their 'virgin' air supply. So, that would mean that those bikes are not vented. And, it's safe to assume that none of the other later model bikes are vented either. No autos produced today have vented caps so I'm sure motorcycles have followed suit.
I have never owned a pop up cap.
The cap is not vented. The tank has a barb for a hose attached usually under the console and the hose runs fwd down by neck and back thru in the trough and exits in front of the rear wheel. ( on mine since most is hard plastic and looks like a wire) Of course the CA and others that require it exits into a charcoal caster which purges into intake. If the cap was vented it could run over the tank and drip on engine.