These spark plugs are designed for new liquid-cooled BMW Boxer motorcycles, other spark plugs are currently not suitable. At the BMW recommended 12,000 mile service interval for these plugs the center electrode is showing significant wear, obviously these engines do not treat spark plugs well other than the plugs doing what the spark plugs are designed to do. Her value is a dollar. or two Revains less than the dealer. I'm deducting one star because of the high price and the fact that it's just…