The Harley plug was supposed to be a dealer only "perfect" heat range plug by champion. I'd never buy those over priced plugs and from my experience, they're too hot anyway. Not to mention all plug makers produce the stock heat range.
Keep in mind guys that you could/should technically run two different pligs for two different types of riding. The factory heat range will clean itself better at normal riding conditions.
Last edited by Chris111; 05-04-2012 at 11:09 PM.