anyone not owning a set of these plugs needs to. I've used these since 2000 in all my bikes. you really won't believe how much power and response they give. most of the new bikes come with them already, but anyone with an older bike eg.f4i, 900, etc.. get them you won't be dissapointed. oh, and sync the carbs/bodies while ur at it, definitely helps. http://www.densoiridium.com/find_part.php