Mario;

The correct technique for a hot restart is to floor it and keep cranking (WITH NO CHOKE!!) until the cool air the engine is breathing cools it down a bit from the heat-soak it is under. If its really hot this may take a few seconds but if your state of tune is fine (and sounds like it is), I think you'll find that it will work every time! Its not impossible, but I dont think its your float valves.

I recommend against a Colortune unless you also have access to a dynomometer on which you can load the engine...otherwise idle is about the only thing you are checking...if you rev and unloaded motor with the colortune installed, your not learning squat (IMHO). I prefer a road test any day...and it only takes about thirty seconds to pull over, pop the hood, and adjust jet height, and close the hoodand get under way again...how can you beat the road test method? Its the: Proof-of-the-Pudding-is-in-the-Eating-Technique!

Cheers