Honestly, it sounds like your out of gas to me. If you replaced the carb, with a new one (?), then it shouldn't be a clogged main jet, which is often the culprit. A loose battery connection can give similar symptoms, I've had that happen to me in the past. Check wiring and connections, atleast that's free. Without any more details it would just be a wild guess.
You need to start a troubleshooting process by elimination. There is a good schematic on how to do so in the shop manual for the Kymco people. If you don't have it, I could email it to you. Just send me your email on a PM.
