Carb adjustment?

[400ex_BG_Rider]

Hi! I'm new here...
I changed the plug on my 400ex and the old plug looked like this:

http://img136.imageshack.us/img136/2796/dsc01168az0.jpg

I think this means it's running a little bit rich, so that means the carb needs to be adjusted! My question is how to adjust it? I don't have a service manual...
Any help or even links are welcome!

[Eviltanker]

http://www.exriders.com/vbb/showthread.php?s=&threadid=221803&highlight=jetting

[400ex_BG_Rider]

10x:D

[Honda#4]

Yea it looks alittle bit rich, try and turn your air/fuel screw in a bit that might make it better.