I finally got my Honda NX50 Express-SR running. It would not start without choking it by hand. Everything pointed to the choke control, but when I bypassed it with tubing it didn't help. I pulled the carb a second time and on closer inspection I found a tiny port that didn't seem to go anywhere, found it plugged and cleaned it out. Now it runs like a watch. What a great little machine, not fast but very quick off the line and smooth as silk.