Fuel tank breather

[Kenny11]

Hi all, had a little ride today, when I got back I could see fuel bubbling out of the keyhole on the filler cap, any ideas? Possibly a breather blocked, but how would petrol get up that high?
Cheers Al

[kinkyfreestyler]

the fuel bubbling is the gases getting compressed as they try to escape through a small hole ,much like when you let a tyre down and you get a wet finger !
Take your cap apart an give it a good clean ,also while you have the cap off give the over flow tube a clean out ,these rot when blocked and thats when the tank starts rotting !

[Kenny11]

Thanks for the info, I'll get on and do that this weekend, where do the fumes etc go normally? Is there a vent on the cap?
Al

[andye]

There is a vent on the cap. A Metal pipe runs through the tank, and out the bottom where a rubber tube is fitted. This is then fed through the frame exiting just above the swing arm.

[Kenny11]

I have taken the cap apart, didn't find any of the holes blocked, but it seems to be ok now.
Thanks for the info
Al