My plugs come out black but on a side note a friend of mine who is familiar with 2strokes was riding behind me and said I might be rich when I had 300's in. But I also think my carbs were crappy. I did get anither set of carbs in better condition so I think I will try the 300's again and go from there. By the way my elev. Is 88ft. But we were riding at the hatfield McCoy trials in WV mountains when my buddy said it was rich so it could have just been elevation. But when I ride again it will be about 80deg 88ft elev. Stock carbs with 27.5P 300M stock needle in middle clip. Mods are cfm air box with k&n filters,LRD pipes,cool head 20cc domes 140psi, +5 timing, mild port