Q. I was wondering if anyone had any opinions about using iridium spark plugs? I have heard that they are better than a platinum but I don’t know if they are worth the extra money? As long as we are on the topic, what do you all think about split fire plugs?
A. Being the owner of a dyno and having made a million dyno runs, the best performance I have seen on the 91-95 7s, and 94-97 9s is a plug that was developed for the 93 Suzuki GSXR 750, the first year it was watercooled. This plug is a CR9EK. Good for about 2 HP. Interestingly enough, Kawasaki started using this very plug in their next generation 9s. This plug has many great advantages, and I will post more on it soon!