Originally Posted by Bikeguy Joe
Sounds like you are a little rich, move the clip up one notch.
If the plug is black and sooty, or oily, you are too rich.
If it's white or very light, and dry, you are too lean.
If it's a little brown, or black/grey with a little oil on it, you are about right.
I second the motion My last bike did the same thing until i moved the clip and and then it ran really nice also make sure you gAp the plug properly the NGK plug in my exp was a much smoother burn