Air filter had a hole, which I discovered after purchasing filter oil. New filter on the way. I'm betting most of the carb work suggested has been done. The bike is supposed to have a Dyno Jet kit in it--or the guy just added the decals, which could happen. Based on the other mods, i.e., bars/grips, etc., I'd say the odds are good that it has the DJ kit. I'll run the old gas out and start fresh to see what's what. Could the popping on decel (not bad, just noticeable) be related to the carb likely being jetted for CO elevations and not our beloved flat lands?