I think my tank has trust issues

[T.M gates]

So I'm out cruising on my 2006 Vulcan 1600, and suddenly she sputters out like I'd committed some kind of betrayal. Figured I ran her dry, okay cool no big deal, I coast to a gas station, fill up… and she only takes 4.2 gallons, like dude...thought this was a 5.3 gallon tank? I dont know how else but is there a hidden gallon she's saving for emergencies (that she didn't feel this counted as), Is the fuel pickup just high, or do these bikes get shy around the bottom of the tank?

 

[TheCasualObserver]

@T.M gates
Oh man, that's a total headscratcher! but your Vulcan isn't alone. a lot of bikes, especially older ones, can act shy around the bottom of the tank. It's rarely a "hidden gallon" so much as a fuel pickup design that doesn't let you drain the tank completely, or a clogged fuel sock on the pump inlet.
Some bikes also have a venting issue that starves the engine as the fuel level drops. Have you checked the fuel filter? That's often the low hanging fruit when a bike starts sputtering

 

[marshmallow]

@T.M gates
Oh man, that's a total headscratcher! but your Vulcan isn't alone. a lot of bikes, especially older ones, can act shy around the bottom of the tank. It's rarely a "hidden gallon" so much as a fuel pickup design that doesn't let you drain the tank completely, or a clogged fuel sock on the pump inlet.
Some bikes also have a venting issue that starves the engine as the fuel level drops. Have you checked the fuel filter? That's often the low hanging fruit when a bike starts sputtering

Ohhh.. OP THIS TOTALLY MAKES SENSE. That's especially considering how finicky some pickups are once the level gets low. I think it could be a clogged sock or filter? I don't know, still not sure unless I go ahead and check everything maybe.