Was looking for the best sparkplug for my Buell Blast. Several enthusiast forums have this listed as the absolute best. I was a bit worried after reading other reviews on Amazon claiming that this plug, IXU01-27, doesn't fit. Unsure, I went ahead and placed the order. I shouldn't have worried. This plug fits perfectly. Added a little nickel anti-seize to the threads, used a drop of loctite on the top cap, and dropped it in. This is the first plug that I have noticed an immediate difference in the way it runs. Definitely worth the $35'ish. Oh yeah, don't try and gap this plug. It is gapped at the manufacturing point. The gap is built in and you will damage the plug trying. If gap isn't correct, contact the manufacturer and get a new plug.