mine does this too. but only if its hot out and it sits for 30 minutes or so. Then its hard to start and idles like crap until it clears up. theres gas on top of my center card and on the bottom of the aircleaner lid when this happens.

its definitely heat related. my carbs are boiling hot. so is the manifold and I have the heat crossover blocked and a valley tray. its heat soaking from the heads (aluminum conducts heat pretty well.

I cant use an insulator as my carbs seal to the hood (340 sixpack) so im interested in ways to fix this too. i can hear the gas gurgling in the bowls