Tuning Issues

So I've been on the forum/had the bike for a while, I've just never been too active. I figured I might finally ask you guys about an issue with my '80 Special II,

It's never ran great but I've been having some major issues with it lately, with the left cylinder sputtering and occassionally not firing at all. I think it might be a carburetor issue, but I can't quite nail down whether it's running rich or lean. It won't run without choke, and will kill itself if I even nudge the throttle. After running for a few seconds though, the revs will skyrocket and almost hit the rev limiter without coming back down.
Not quite sure what's going on with it, but I figured some of you guys could point me in the right direction.

Lean if it needs choke to start. Possibly gummed up idle circuit in the carbs, at least. Tear them down, clean out the pilot jets, and everything else while you're in there.
Check the carb holders for air leaks. Before you take the carbs off to clean get it running and spray some carb cleaner or wd40 on the carb holders. RPM may change noticably if there's a leak. A visual inspection for cracks helps too.

Sounds like the throttle could be sticking, or the idle set screw is improperly adjusted.

Have you done any sort of recent maintenance? Carbs should be thoroughly cleaned at least once a season. What do your plugs look like? Have you checked the timing at all? Adjusted valves?

Running no mufflers or any air filters and intake pipes will cause lots of issues.

These can certainly be fussy. I have a 80G that ran beautifully into late fall. I took a ride thru the wet grass in the yard without the bike even running- front wheel hit a slippery rock when I was turning and pitched me off, cracking 2 ribs.( 2 weeks before open heart surgery) I picked it up and parked it for the winter and now I can't get it to run..great spark, valves are perfect, super compression numbers.time to pull down the carbs once more....you get used to it after a while. Good luck!