'82 KZ1000 Running Rich (I think??)

I have a 1982 KZ1000 Police bike that recently started running poorly and then stopped running all together. I'd like to get some pointers before I dig into the carbs since I live in an apartment complex where working on vehicles is prohibited and want to minimize the time it taken apart (yes I know... I'm trying to find a new place).

Here's the story:
The bike was partially disassembled and not running for some years. I bought it, put it together, it ran but very poorly, I took it to a shop that came well recommended for tuning... After coming back from the shop it ran great but still had minor issues I decided to fix myself (electrical, sticking brakes, etc)... After a few weeks of only riding around the block, etc to test fixes I got it ready to go... After just a few longer rides around town it began misbehaving... Seemed like it was running rich... Got worse and worse and finally died and would not restart a few miles from home.

Upon getting it home I found the plugs were fouled in all 4 cylinders... This has got me stumped since there is virtually nothing common the the cylinders that could make it run rich except the air filter and it is clean and brand new. Not jetting either because it ran great before... What gives? Am I missing something obvious?

Thanks

Like to see pics of the plugs. I suspect valve guide seals, not being rich. Before I was able to redo my valves,springs and seals, I was running BP 8 ES plugs or platinum. I would clean them every 400 or so miles. The BP plugs have a deeper reach so they would more or less clean themselves.
Steve

My plugs are BP8ES as well... Here is a pic.

Never really noticed any evidence of smoking and I have well under 400 miles on the bike (MAYBE 80-100). That said some of the sooty material seems awful liquidy after all this time and I would think if it were gas it would have evaporated (there was a significant gap between when the bike stopped working and me trying to fix it because of weather).

I will try cleaning them and see if it runs... That will tell me if my issue is just plugs.

Those short runs to verify a repaired fix does not allow the engine to get hot enough to burn off the carbon on the plugs. If you keep doing those short runs then over time the carbon on the plugs will foul them. Try to ride the bike each time long enough so the engine gets to operating temps. Also do not run the choke for long or it too will foul your plugs. When I fire up my bike first thing in the morning I will go to full choke then as soon as the bike starts I turn the choke off and modulate the throttle to keep it running. A LOT of people will keep the choke on full until the engine will idle on it's own. Again over time that will foul your plugs. Don't be one of those guys.

Maybe my problem is just improper riding practices then... Wouldn't that be nice!


Got the plugs soaking in some cleaner now... I will give it a try afterwards and if the problem goes away I will try to avoid excessive choke and short rides.