MC Dies upon ANY throttle application. HELP!

Agree totally with Ted's answer old fuel causes all manner of problems. I have seen this happen many times over the years of riding bikes and other petrol engine run machinery.

Petrol lasts about 3 months normally then the stuff goes bad and coats all surfaces it is in contact with a brown almost varnish like coating. Jets and small bore orifices get blocked. A total strip down of the carb[s] is sometimes necessary as trying to to use solvents or airlines will not clear the blockage. You can try carb and choke cleaner spray if you are not confident on stripping down the carb[s]. Remove the carbs from the bike and spray into every hole you can find remove pilot air screws and clean them thoroughly.

Last but not least drain the carbs and tank, half fill tank with new fuel find some in tank fuel system cleaner these will work with carbs and injectors. Use about half the bottle ans see if the engine recovers as you ride. Good luck

Odds are that if it sat for a year with fuel in it, the carb may be gummed up. Opening the throttle will cause an immediate engine stop if it is not getting fuel.

I'd recommend a "clean out the carb" project, including using air to blow out allof the small orifices.