As the title says. The bike will fire, it just kills itself almost immediately. I had this issue before after garag'ing the bike for some time, I had a new carb lying around so I replaced it and it ran just fine. But this time I don't have a new carb. It is worth noting I'm using very old gas (been in the garage for about 2 years). I suspect all I have to do is clean the carb out, how does one do this?