So, I kept my moped in my basement over the summer, and now it's not running anymore. I cleaned the carb to the best of my ability, tightened loose screws, checked the fuel line. If I run the moped downhill holding the comp, and turn the throttle, the engine sounds like it's working, making a nice put-put like it does when it works. The moment I let go of anything, or the bike stops, the engine dies. Even while the engine is making the sound, I don't feel the bike pulling, it's just gravity.
I put gas directly into the chamber, and the bike pulls then.