My 1982 Honda Urban Express NU50 is behaving strangely. When I try to start the moped, it will idle for 5-30 seconds and then die, if it even starts. If I give it gas while it's running, it dies. To try to solve this, I took it apart and cleaned out the carborator with carb cleaner by spraying compressed air through it. When I put it all back together, it started right up and ran perfectly. I rode it around my neighborhood and it died a few times, but overall ran pretty well. Whenever it died, it would start right back up.
Fast forward 3 hours, when I went back outside to try to start it again. I'm back to where I was before the carb cleanout. This is killing me. What could possibly be wrong? It ran fine, then 3 hours later, I'm back to where I was before the carb cleanout? Right now, I'm playing with the idle and throttle stop screws and it's not starting at all, no matter where I set them. Anybody have any idea what could be wrong? I have fuel, I have air, I have spark. There's nothing else to it, but it still doesn't go. Help please?