I live in East Tennessee but go out to Salida every 2-3 years. I was told to go 5 sizes smaller on the main jet and 1 size larger on the slow jet. That was too lean for me and causing the bike to overheat. Now I go just 2-3 sizes smaller on the main. Regardless of how well you jet you will lose power and gain gas mileage. My 300 would get 40% more mileage but ran like a 200.