Vacuum in gas tank?

[TURBO200R4]

there is a little leaf cutter bee that likes to build a nest in hoses around here also on cars and trucks you can get mud on the trans vent and when the mud dries out it will plug the vent so when it gets hot it will push the atf out the filler tube.

 

[cardinal93]

@tdragger unfortunately I can't remember off the top of my head and my bike's still dog paddling across the Atlantic so I can't go look I'm sure one of these professional rocket wrenches will know though

 

[Boog]

My R3T does not have the same filler cap as yours. I have taken the tank down to fumes a few times on long rides and do not sense a serious vacuum when I unscrew the cap. I did have an issue last summer when I over filled the tank causing a serious loss of power until I opened the tank after the first few miles. Once the guys identified that I was over filling it and I stopped topping it off, the issue went away.
As for the insects others have mentioned, I sure wouldn't rule that out. My bike is ridden just about daily and I often find some sort of bug under the cover in the morning from spiders to wasps and a few odd beetles. This time of year I look for them whenever I do my safety check; I’d hate to have a creepy crawler wiggle under clothing or get in my helmet during a ride. So having something clog a vent tube is surely not out of the question.

 

[TURBO200R4]

for what it is worth.
i used to have a lot of gas in an under tank and to get it out i would use a 55 gallon drum. i would run a hose into the under ground tank and the other hose to the intake of my el camino. i went inside for a coffee break and when i came out the 55 gallon drum had imploded (crushed). so if you like your tank be careful.