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Do you know any of the history of the bike ??? , like why it was parked ??? , was it having these kind of issues before parking ??? , if so I would look at the stator , or maybe clogged vent line in the tank ..... Also if you replaced the carb but used the old vent lines , it is possible that mud daubers got into he lines at the end , and are clogging them ....it is real common for them to get into hanging vent lines , when a bike sits , especially if it is in a place that is open or partially open where insects can get in
But if you completely replaced the carb itself and the issue did not change , then I would first look into the electrical (stator output), coil output , spark plug cap .... then move to vent lines , etc. .... those bikes are pretty bulletproof , they seem to last forever and usually will run for years without issues , so I would look into why it was sitting , and the actual sitting as a reason .... so insects , or maybe even a rotten rubber in the fuel valve itself (on/off/reserve) and its just not getting gas into the carb , or minimal .... what about air filter ?? , remove it and look into the snorkel on the intake side of the air filter box , see if there is something blocking or nesting in there like mice or something ...