Did you check the reed valves while the carb was off? Those could be an issue.
Next is if the reed valves are okay, sounds like your needles are way out of whack. Start at about 1 1/2 turns out and go from there; high adjust first, then low, then back to high. Check the transition, if it dies it's too lean, if it does a lot of burbling (some is necessary and acceptable since there's no accelerator pump) it's a bit rich.