after reading everything on here and reading all my own thread over pretty much if you got the money and the correct jetting run race fuel.. if you dont want to mess with jetting just run pump gas. As my bike is jetted great i been running U4 in it im bout to buy U4.4 does anyone know if ill need to mess with jetting again or not? Once i jeted my bike running U4 i have not yet once touched the choke and starts by 3rd kick. im 210lbs and my bike has no problems pulling me all over the track. Im sold on race fuel!