California fuel tank nozzle

[Firehawk068]

The valve was not made to vent fumes to the atmosphere. 

Where do you think they go?
If you didn't have a tank vent, when your tank gets hot, you would overpressurize your fuel system, and your carburetor's inlet needle valves wouldn't be able to stop the fuel bowls from overfilling.
when the tank cooled, it would create such a vacuum, that it could possibly crush in on itself.........(Don't doubt this can happen. It's happened to someone on here)
The fumes exit through the flapper valves, and out around the top of the fuel cap, and out to atmosphere. Any fuel that comes out with it, flows down the little hole(gravity), down the tube and out the back of the tank, down the little hose, and forms a puddle under your bike.
Hope this helps.

[AustinFJ]

The valve was not made to vent fumes to the atmosphere. 

Where do you think they go?
If you didn't have a tank vent, when your tank gets hot, you would overpressurize your fuel system, and your carburetor's inlet needle valves wouldn't be able to stop the fuel bowls from overfilling.
when the tank cooled, it would create such a vacuum, that it could possibly crush in on itself.........(Don't doubt this can happen. It's happened to someone on here)
The fumes exit through the flapper valves, and out around the top of the fuel cap, and out to atmosphere. Any fuel that comes out with it, flows down the little hole(gravity), down the tube and out the back of the tank, down the little hose, and forms a puddle under your bike.
Hope this helps.

They go to the valve at the front of the tank.   

There are 2 vent/drain holes at the filler in the tank.  There is a drain at the side to drain spillage and or rain/wash water.  This is piped to the back of the tank and does connect to a hose and spills on the ground in a little puddle if you miss your filler hole or you have no gasket on your filler cap.  There is also a vent hole at the back of the filler that when your filler cap is open you will/should see that it has a rubber grommet so that it seals to the cap when closed.  This vent is piped to the valve at the front of the tank.

So if your scenario works on your bike, you are missing the rubber grommet the seals the flapper vent in the cap to the vent hole/pipe/valve at the front of the tank.   

My statement has always been in this that the flapper valve does not vent fumes to the atmosphere.  And by design it does not.  It vents them to the valve at the front of the tank.  On CA models, that valve is connected to charcoal canisters.  In either case,the flapper was not made to vent fumes to the atmosphere.

Hope this helps and you get your bike fixed so it doesn't leave puddles under your bike.

[Firehawk068]

Wow Tex.....
Thanks for diagnosing  a problem that doesn't exist on my bike......
I was responding to Silas, where he asked "how do the NON ca bikes vent"
Mine is NOT a CA bike. I do not have the extra vent tube on the front of my tank.
My tank vents directly to the atmosphere, and works exactly as intended when they built it.
Sorry that you misunderstood my post. I was trying to help Silas.

[AustinFJ]

Wow Tex.....
Thanks for diagnosing  a problem that doesn't exist on my bike......
I was responding to Silas, where he asked "how do the NON ca bikes vent"
Mine is NOT a CA bike. I do not have the extra vent tube on the front of my tank.
My tank vents directly to the atmosphere, and works exactly as intended when they built it.
Sorry that you misunderstood my post. I was trying to help Silas.

My apologies.   I had commented earlier in the thread and with the subject still saying "California fuel tank nozzle", I thought we were still talking about the original subject.   Missed the switch to non-CA bikes.   My bad.

[Tapartacus]

ok so my fuel cap leaks gas through the key hole after I fill it. How do I stop this? It doesn't leak when the tank is half full. Btw it whistles(sings) as well .
A

[silas]

I'd take it apart and clean it.

There's a tiny spring-mounted ball bearing that serves as a valve on one of the vent holes. Be careful not to lose it.

[RichBaker]

Big clear plastic bag is the best thing to take it apart in, anything that goes flying will stay in the bag..... Gallon ziplocs work good.