If you left it sitting, uncranked for a year; unless you shut off the fuel and either drained the carb or ran it out of gas, your carb most likely has a coating of varnish (gasoline residue) in it -- the very tiny holes in the jets are glazed over. One quick check is to try priming the carb - if it cranks and runs until the primed fuel is used up and then dies , you need to clean the carb.
