I meant with my tank off the bike the fuel flows with vacuum on Res but prime does not work on or off the bike so I use Res not enough gas to try On setting but assuming would work to. The new fuel tap coming will solve the prime issue but not the fuel flow to carbs I'm assuming.The needles must be stuck when it did run a short time throttle was unresponsive.Confused ! your saying your not getting fuel flowing to the carbs - that would mean your not getting fuel coming from the tank to the carbs ?
Or in the lines - are you saying your not getting fuel come out of the lines when disconnected and in the prime position ?
You should get fuel to flow into your carb bowls unless all needles are sticking.
As rbrralph says open bowl drain and see if fuel come out when tap in prime position.