I have gas leaking out of the air filter. It is flowing out of the carbs. I have cleaned out the carbs but it keeps leaking out. 

I am no expert but I think that is a float issue. They must be stuck open.

That might be it. How would I test that on my work bench?

I would check the Wiki about setting float heights. I believe you flip them upside down and then measure. The wiki or a few searches should get you the numbers as asll as some pics. You can also test them on the bike with a short piece of tubing. see: http://www.gstwin.com/float_height_check.htm

Thanks Ill try that!

Replace the float o-rings and seat o-rings too. Killed that leak!!!!! Now it idles up at a stop?

did you set the correct float height when you replaced the seats and needles?  if not this could cause your high idle. correct float height is 14.6mm + or - 1mm

Im new to this carb thing, how would I do that?