1985 GL1200 LTD Idle Problems

Hi,

My 1985 LTD Goldwing has always had this weird idle problem, but I haven't really taken the time to figure out what it is. It runs fine once warmed up for the most part. However, when it's idling or cold it doesn't seem to be consistently firing on all cylinders. Sounds like one of the left-side cylinders is firing late or getting too much fuel (sitting on the bike facing forwards). That doesn't bother me too much, but I have a feeling it's connected to why the bike has trouble idling in the cold.

Anyways, I took a video of this and here is a link to it:
http://youtu.be/bqRAGVL4Uqw

In the video it's at 900rpms cause the engine is still cold, but before I fiddled with the screw I mentioned in the video and the idle screw in the center of the bike it was just stalling out. It comes up to around 1,100 rpms now when warmed up.

Let me know what you think or if you have any ideas. I did change the timing belts when I first bought the bike, but it's been pretty much the same since day one so i don't think the timing is off. When I bought it the idle was actually set a bit high around 1200-1300 rpms so I figure maybe they had done this to prevent it from stalling when cold. There are no error lights coming on on the computer under the trunk. It has 43,xxx original miles.

Any ideas or things to try is greatly appreciated. Also, as a side note, the exhaust smells pretty bad, like it's pure gas. A very rich smell. Almost enough to make your eyes water. Also, when the engine is above 3,000 rpms it seems to vibrate. Pulling the clutch in and letting the RPMs drop down makes the vibration disappear. It's more like a buzzing vibration which might be normal but I've never ridden any other Goldwings. Maybe related? It vibrated the same before and after changing the timing belts as well as changing the u-joint and lubricating the driveline and seems to be completely engine related.

Thanks!