This to me sounds like you need a carb cleaning. If you have let the bike sit for an extended time the carberators maybe clogged or gummed up. This has to do with the new gas that is out there now. It is cheap and with the introduction of Ethanol alcohol now it is even worse on being stable for long periods of time. I have seen fuel go bad in as little as 3 weeks.. One quick check you can do is open you fuel tank and smell the fuel. IF it smells like varnish it is probably bad. You can drain the tank and add new fuel and that should solve your problem. Keep in mind, that the carbs need to be drained as well to get the old fuel out of there also. Make sure you have a battery charger going when you start crankin that puppy, because you will need lots of extra juice to get that baby to fire up. If it is starting now and runs on choke, that means your idle jets are clogged. Best repair is to remove carbs and clean idle jet. Unless it is fuel injected.
Let me know how that goes and we can proceed from this point. I am a certified mechanic from MMI as well as a HDTV GURU. Smiles. have a good one.