Brandon, From Vulcan forum, one of the hoses that are hooked to the carb is a vent tube and may run up and under seat, if this hose is plugged or pinched it could cause similar issue to what you are experiencing. Links below discuss the issue you are presently having.
Check the attached links,instruction and guides,also you can also google (Kawasaki Vulcan flooding rear cylinders) for more info.
Good luck
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