REPAIR

Have you replaced the fuel? petrol goes bad when left for a long time! If you have a good spark at the plugs it may well be the prob.

Most likely the fuel system has become clogged, because when gasoline sits for long periods it turns into a varnish type liquid and clogges up the entire fuel system, Remove the carb,air supply intake box and spray a shot of starting fluid into each air flow port on the carberators now try to start the bike once agian if it starts but shuts back down your fuel sysrem is clogged and the entire system from gas tank to the carbs must be flushed thoroughly and rebuilt.

no, I am a complete drivetrain mechanic small engines motorcycles lawn and garden equipment and automobiles from Gwynn oak , Maryland