i have a tilly 212 on which i just installed a billet flywheel, it ran great for a few lapd around my yard before dying and unable to be restarted. every time i try to restart it, all it does is run for a half second and then immediately die. if i get throttle on it, it backfires through the carb and smokes through the air filter before dying. it seemsike the ignition timing went off while riding but im not sure because it was running perfectly fine before