Fuel tank boil over?!

[jdm5770]

I could use a little advice. Yesterday I road to the DMV (a 45 min ride) walked in, renewed my license and walked out. It was a pretty warm day, about 85 and when I left my house I filled the tank...not too full, it was on the side stand and I filled it just below the cap. Anyway, I jumped on my bike and fired it up....and tried again, and again....finally, it started up I thought this was a little strange, especially since I was just on it and it was warm, normally she starts right up. Anyway, I made it about 5 feet when the bike dies and fuel starts pouring out of the overflow line that goes over the air box. I pull her to the side and opened up the gas cap wondering "what the crap" As soon as I did that fuel boiled out of the tank and all over my bike. 30 minutes later, she started right up and road fine all the way home.

Has this ever happened to anyone? Shouldn't there be something to release the pressure in the gas tank? If there is, whatever it is isn't working on mine...help please, I'm at a loss. Thanks!

[Black_peter]

There should be a vent. Sound like the hot engine heated up the gas and the tank couldn't vent.

Check all the tubes that should end up under the bike by the swing arm. There should be an overflow tube (from the filler neck, for rain of over fill gas) a tank vent to allow expanding air and gas vapor out (and air to replace the used gas in) The Air box drain (that one should be plugged, that one is fro draining oil and water that builds up in the air box, it's pretty big maybe 3/8 dia) make sure all the tubes are free (no kinks) and if you can identify the tank vent try blowing air through it. It might have crap or critters in it.

[jdm5770]

Thanks BP, that's pretty much what I expected, the vent line must be clogged.