Pressurized Gas? What could cause that?

Just sent my friend home after attempting to fix his bike for like 5 hours. I think he has some sort of air leak problem because the motor likes a rich setting on the carb needle, and it likes to over-rev once you let go of the throttle for a few seconds. Changed the carb, switched out carb, exhaust, & lower cylinder gaskets, and etc. Also cleaned out the exhaust. Nothing changed at all. Plug chop obviously results as dark because we're forced to use a rich setting. Fuel ratio is 32:1 (4 oz/gallon), so I doubt there's too much oil.

On his way home he just called me and said the engine over-rev'ed a lot more than it was before, and gas started flowing out of the cap. What does that mean?

Venice Motor Bikes said:

Dirt in the inlet needle will cause the carb to flood like that.
Also, don't use a wrench to tighten the top of of the carb! only hand tighten it! Over tightening can cause the carb body to warp & the slider to stick open!

Click to expand...

Really? There's like a special wrench attachment and everything but ok I'll try it.


By the way though, I meant the GAS CAP on the tank, not the carb's cap. Sorry my fault I didn't specify and I doubt anyone would assume that's what I meant, but it is.