Heading to the DARKSIDE!
Join Date: Sep 2009
Location: Northern Kentucky/Burlington
My original '86 tank was just like that. YES.....The early tanks did not have the internal vent tube!!! That is why I went with a newer model tank with the tube. When I filled up the tank on hot days under the awning at the gas station.....everything was fine. As soon as I would pull out from under the awning in the sun the sun's heat on my black gas tank would make the gas expand and go through the cap drain to the non existent tube and pour all over the top a side if the tank pouring on the hot engine. Your bet solution is to take the gas cap apart and clean all of your air passages really well with carb cleaner and a tooth brush. My bike eventually did what yours is doing and when you would park it, you would hear a faint whistling/squeeling sound coming from the gas cap. It was the pressure difference.....very slowly equalizing.