My 89 must be blessed as I am not a slow or easy rider and I check mileage about every other tank and get a consistent 39-41 mpg. Average speed driving to work is either 65 or 70 depending on whether it is 2 lane or 4 lane highway. On the 2 lane I pass quite a few vehicles by down shifting to 4th, getting around them and back on my side of the road then back to road gear. I do run an ounce of Seafoam once a month thru the gas to keep things clean. Air filter gets cleaned or changed annually. Oil gets changed every 4k miles and I run with Mobile1 10w40. Tire pressure is checked every week and I run 2-3 lbs over spec.
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