That's a vent line and you can just run it down between the cylinders. That line usually hooks up to the backing plate of the air cleaner when you have the stock one or aftermarket cleaner that has a connection on it.
so the front one hooks up by the back of the carb and back one to nothing. Just making sure I get this right. I noticed the line coming from the front head is smaller in diameter than the back. Thanks Brew
