Can somebody please give me a final word on the best spark plugs for a 1998 Buell S1?

K%26amp;N air filter and Vance Hines slip on. Rides great but I want whats best and reading every site available but no testimonies!|||They use the same plugs as the Vrod. They are slightly different than the Sportster. I always went to the dealer and used the factory plugs in mine and never had an issue. You can find them cheaper, but they are still so cheap and replaced so seldom, I just went for what the owner's manual recommended.|||The one with the proper heat range and indexing. Never indexed a plug? Not too sure what heat range is? You've got some reading to do.|||Use Iridium spark plugs, will provide a much stronger spark. You might want to fit a set of Taylor HT leads as well.|||NGK. Don't waste your money on platinum or iridium.