How can I vent my gas cap?

[gringostar]

Hello,

My Agility 125 goes for about 15 miles and then it dies.  If I open up the gas cap it runs great.  If I run it without a gas cap it runs great. Clearly the gas cap is not vented.  How can I remedy that?  I don't want to spend $30 for a new gas cap.  I may go to Lowes or HD and buy a vented gas cap for a lawn mower. But, that will cost $10+ USD.  Can I drill it out?  Got videos?  Links?  Pics?  Thank you from El Paso, TX. 

[Stig / Major Tom]

I think you can drill a small hole in the cap....but you'll have to turn yourself in to the EPA.
Stig

[CROSSBOLT]

Very small hole, no bigger than 1/16" will do. You will have to study the cap carefully. I cannot recall how the Agility cap appears.
The problem is caused by the vent valve sticking closed.

[Stig / Major Tom]

Very small hole, no bigger than 1/16" will do. You will have to study the cap carefully. I cannot recall how the Agility cap appears.
The problem is caused by the vent valve sticking closed.

Also, good idea to remove cap from tank before drilling. (Legal Team added this)
Stig

[CROSSBOLT]

Stig gets it! Remove cap! Har, har!

[Vision]

I believe there's a vent separate from the cap, a tube. Check that. Check the peacock. I wouldn't drill into the gas cap. Hit a bump and your butt can catch fire.

[CROSSBOLT]

I believe there's a vent separate from the cap, a tube. Check that. Check the peacock. I wouldn't drill into the gas cap. Hit a bump and your butt can catch fire.

Yep, there is a tube. It goes to the vacuum operated vent valve that sticks shut andvstarves the engine of fuel. I have vented a Genuine Buddy 150, a Yager 200i and a Downtown 300i. The Buddy gas cap WAS under the seat but no burned butts!