I am running HD 6R12 plugs just like the book calls for. When I pull my plugs they are "egg shell" to white in color. Nothing I do will make my plugs tan in color. I have cross checked my A/F ratio with two different instruments and the engine is not lean by any standard. I just can not figure this out. My A/F ratio at idle is in the low 13's. Cruise is mid 13's and WOT is mid 12's. If I had an air leak it would show up on the the Infra-red exhaust analyzer. The bike runs great. I have no concerns at all with it's performance. Starts great, pulls strong to red-line, idle is great. As a matter of fact my gas mileage is only in the mid 30's which by itself should make the plugs tan.. but they are near white.(both front & rear) What gives? I just can not understand it. Does anyone REALLY have tan plugs (front & back) when they check them. Only FI bikes please..