SO there's three points where tubes span between the carbs with vent thingys on them. The bottom one is for fuel, and then there's a middle one and a top one, we think the middle one is just a vent, and have no idea about the top one. what are they guys?

here's a pic of the top one so you know what i'm talking about. This is a 2004.

Nevermind! i got it figures out. It runs soooooooo much better now. the only thing is that it has this weird thing where it seems like it stops firing for a quarter second and the rpms drop, then it's right back to chugging along. anybody know what could cause this?