what kind of oil are you using Dave? you have a great amount of carbon build up on yours then my... i am using castrol racing 2T full synthetic, i am getting 0 carbon on the ground casing of the plug. everytime i take them off to have a look i get a silver ring, but the center and the ground electrode is dark brown. i saw on some plug reading pages it means i am jetting lean... but i am thinking it has to do with the oil i am using.
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