OK , do you say you get between 36 to 38 in Lubbock but I think you are saying that at altitude you get a lot better. Maybe up to 50 mpg. I can maybe believe that. The O/2 sensor adjusts for the thinner air and therefore leans out the mixture to compensate. So are you making less power also? I've never been out west with the bike. And I don't recall questioning you about your mileage. I guestioned the guy that got 56 mpg from Ohio to Tennessee and back. I don't recall any mile high mountainous regions in those areas. 36 in Lubbock and 53 in Colorado is a big spread. I never noticed my fuel mileage increasing out west. Usually takes more throttle to make the same power. Basically negates the thin air thing. You're bike is obviously exceptional at times.