I bought a used shee with rad valves I also have VF-2 that needs new reeds. Would I be better off to change reeds. The bike has fmf fatty pipes,coolhead 18cc domes,stock porting,28mm flatslide carbs,open lid on airbox and 20 over fresh bore.
Check the cable adjustment at the thumb throttle. Also spray carb cleaner around the carbs, intakes and cylinders to check for air leaks. If the motor revs up you have a air leak there.
Does the dead cyl stay on the same side when you switch carbs and plug wires? Is this a new build or did it run right before? The popping and bogging sounds like a air leek or wrong jetting.