I took my 650 to the dealer and they kept it for three (3) weeks due to preshure building up in the gas tank.. when i finly got it back they asured me it was fixed, but its not! im tired of dealing with them, so can i dril a small hole in my gas cap to alow air to excape but not wasteing gas?

 

Did you check the vent line?

 

There is a fix for that vent line. Do a search on here and you will find it. I took the easier route and drilled holes in my gas cap. If you look closely at your cap, you will see you can take it apart. I took mine apart and drilled a few holes in it. When I put it back together, you can't tell I did anything to it cause you can't see any holes. I don't have any pressure problems now!!

 

The check valve in the gas tank breather line can get clogged or malfunction. You can replace it with a small fuel filter or run the line up to the handlebars where the other 4 breathers are. the fuel filter idea is a semi fix since it will get mud out and not let water in fast enough to do much, but I like the breather line idea best.

Holes in the lid isn't my favorite idea, it proly works pretty darn good, but I have had my gas cap under water quite a few times and I would rather not drill.

 

This may sound like a dumb question, but how do you know if your gas tank is building up pressure inside? What kind of symptoms/problems did it cause?

Whenever I remove my gas cap, I usually hear it sucking in air like it was a vacuum inside. Is this normal or not? If not, what kind of problems will it cause me?

Happy trails...[img]i/expressions/face-icon-small-smile.gif[/img]

 

Mikeyboy, the sound you are hearing when you open your gas cap is probably pressure venting out, not in. The problem with pressurizing your fuel tank is that it can overpower your fuel system and literally force fuel into your carbs (and engine) when it is not running. A few guys here have had problems with their engine oil having a gas smell to it. Overpressurizing of the fuel tank is the cause of this.

 

One thing is for sure, if you drill a hole in the gas cap and get in a situation like I was in last weekend you are in deep trouble.

 

UH, yeah, like your bio picture shows?![img]i/expressions/face-icon-small-shocked.gif[/img]