I´ve had my GL500 for 20+ years. At any speed above 55 it starts starving for gas. I have replaced the gas tank, fuel petcock, and all fuel/air lines. Sometimes it will run perfect for 30 miles then start acting as if it is running out of gas. Twist the throttle and it does fine until you turn it loose. At other times, if you turn into the wind, or have a side wind, it will starve for gas, but as soon as you turn with the wind, it runs just fine. I am so lost as to what could be wrong and hope someone out there can help me.