750 Brawler vs 650 AVS 2 at the track, right OOTB !

The AVS appears to be a nice carb for the 384.00 shipped to your door price. HOWEVER, of the 2 carbs, I was surprised that it was the AVS that started some hard and actually did after a burnout.
It shouldn't which means you need to figure out what's wrong with it. My guess would be to check the float levels first.