Worn reeds causing rich condition?

[jb_dallas]

I have read a few threads about how worn reeds can cause a rich condition, but I have not seen it explained. How does this occur? I dont necessarily doubt it is true, but I dont understand how.

Thanks

 

[jsantapau]

the reeds act like a one way valve to keep the pumping air of the 2 stroke from backing out to the carburator. the carburator jets does not know which way the air is moving only the signal it gets. So air come across the jets the 1st time in a normal fashion and picks up some fuel, then the air goes backwards thru the carb picking up some more fuel(not as much since the carburator design is one way to optimize the airflow signal to the jets) then it gets sucked back in picking up even more fuel.

hope that helps

 

[digifox]

Yeah pretty much what ^^^ said.

And a worn reed does not close as fast as a new set.