I'd veto that notion about running the engine in a dark room/garage unless you really are aware of just what you are doing and take the proper precautions. Otherwise, in just a short time (depending on room size and other variables), ALL of your performance issues will disappear.
Carbon monoxide is a deadly b!tch. And, unfortunately, an older bike with fuel delivery and/or ignition issues in a questionable state of tune can only exacerbate that killer.
You've given no history and just a few very recent symptoms upon which to base a diagnosis. If the bike will start and run for a little while, then I agree with the above posters who suggest starting with the fuel vent and work your way inbound from there. Choking from too much fuel and fuel starvation can both mimic an intermittant ignition problem.
Given your limited amount of info, I think your Honda is running out of gas.