I am in the process of replacing my trans from my 99 F4. I checked the plugs and each plug has a ring of oil on the base and a little bit of oil in the threads. Does this mean worn out rings? Bad head gasket? It's not the valve cover gasket cause the cylinders where the plugs sit it I put a clean towel down them and pulled it out and each one was clean so the oil isn't coming from the top. Also when I was riding the bike it ran great. No problems starting or anything like that.

 

To determine whether or not your rings are worn would entail taking a cylinder compression test. If the results are a bit low, you can pour a teaspoonful of engine oil into each cylinder and re-do the compression test one at a time . If the readings go up, then that usually indicates worn rings. The valve guides could be worn also, which is usually indicated by blue smoke from the silencer as you shut off the throttle whilst riding along. New valve guides and/or valves are the only cure for this, depending on the severity of wear between guide and valve. If the plug tips are not wet with oil, then I wouldn't worry too much just yet. If you start to get a lot of blue smoke from your silencer all the time, then it might be worth investigating further, especially if you have to top up the oil frequently.

 

You basically described my plugs.

I was worried but it runs just fine and doesn't consume oil at all. I now think It might be running way too rich all this time because the exhaust tip is quite black. The F4 will get an overhaul after the Bird so maybe I'll find out then.

Let me know what you find because I'm interested in finding out what's going on.