I purchused a 77 puch maxi 2hp last summer. the engine was siezed up and had been sitting outside for ten years so i rebuilt the engine. it starts and idles fine, but when the moped is down it wont rev, it will just bog and die when i give it gas. if i plug the carb right it seems to rev better. i cleaned the exhaust got new gaskets and nothing has changed. can someone tell me my probolem?