Sounds like sitting to me, when I bought my 95' XI I didn't bother to check the gas before trying to turn it over and paid hell for it. Alot of water had settled to the bottom and fresh-ish gas was on top so it smelled fine, the engine ended up sucking it into the cylinders and as White knows it took me at least two weeks to dry out

I'd pull the plugs and see if your plugs are getting moist or nasty before you go tearing into the carb. With mine it would sometimes fire up, dry out the spark plugs then refoul all over untill I drained all the gas out. Either way it sounds like an easy fix

Best of luck.