I've had ongoing issues with a fuel problem on the lower end, the engine bogs I hit the choke and it clears up. Has been running good at the 3000 3500 range and now it's dropped 2 cylenders while running. I've had the carbs rebuilt about a year ago. Yesterday I ran on auxliray tank to isoltae my main tank, Now I believe it's elec. after 10 minutes of running it does the same thing. Both plugs on the right head are dry. Any suggestions from this point?