High Pitched noise coming from gas tank!!

[Joubsta21]

I was wondering if anyone has ever experienced a high pitched ringing sound that's pretty soft but annoying coming from their gas tank? I've noticed a couple of times after I've gotten back from a ride and the bike is turned off, I can hear this noise coming from the gas tank. I'll open the gas tank and a lot of pressure will be released. I was just wondering if anyone knew what could be causing this!
~ Thanks

[Rune]

Sounds like a build up of evaporated petrol or the expansion of petrol in in combination with a little air in the tank. If it's very cold out, the heat from the motor will make the petrol expand a bit more than on warmer days because of the difference in temperature.

I think it would be a good idea to check the gaskets see if they are going, you don't want petrol all over all of a sudden :wink: .

[zx6man]

most bikes have a small hole in the filler cap, to allow these build ups to escape and to cause the whistle. Perfectly normal it is.

[mysteryjimbo]

Mouse nesting??

:lol:

[21QUEST]

Fuel tank breather hose? you might want to check it's not blocked.

Cheers
Ben

[BillyC]

Fuel tank breather hose? you might want to check it's not blocked.

Cheers
Ben

Sounds the most likely to me!

[Rocket]

Could be a Squirrel storing nuts in your airbox?

[zx6man]

all fuel filler caps have a hole in them, other wise the vacuum would build up and no fuel would travel down the fuel lines to the carbs. The Zx6 whistles like a good un sometimes.

[Carsick]

Every bike I've ever owned whistles on a hot day, I just find it entertaining.

[zx6man]

Does anyones play an actual tune....??? :D

[Barty_b0y]

Every bike I've ever owned whistles on a hot day, I just find it entertaining.

So you dont own an mp3 player then :D :D

[embee]

...remember Joubsta21 is in California, so it'll be an evaporative loss canister model, and tank venting will be via the can. Not sure what they have in the way of valving, but it's normal to run such systems with "some" tank pressure to reduce the evaporative losses.

I'd guess it's just the vapour pressure overcoming the check valve and venting to the can.