2014 FLHX - completely stock I want to change my exhaust not for looks or sound, etc., but efficiency and longevity reasons. I wouldn't mind it being louder but I want to get about the same fuel economy (about 40 mpg) while reducing the factory "lean" condition. Better performance would be great, but not at all my main concern. I know I would have to have a tuner and retuning done. Do I have to purchase a new breather setup? Am I correct in saying that all stock bikes run too lean? It seems I have read that in countless posts. Thoughts would be greatly appreciated. Thanks!