Not my first honda, but first 400 ex(2003). Runs great, starts great, but can't get fuel to stop flowing from the overflow tube. I already disassemble the carb, cleaned it all thouroughly, check the float n seat, reassembled. The darn thing still overflows. I submerged the float in water(no leaks) and bought a new float needle seat. The darn thing keeps overflowing from the float vent tube. What gives? Its non-adjustable, so how do I stop this from happening?