My personal observations are similar to eemsreno. While doing back road riding, even quickly, I was seeing 53mph on the dash. This was confirmed at the pump with calculations. Computer mileage changes quickly after a reset, but much more slowly as the miles build. I've also noticed that the dash mileage is more accurate when I ride more, steady speed, highway. In town, stop-n-go seems to confuse the dash mileage, and is overly optimistic. My Jeep's dash mileage is exactly the same way. 60mph or less seems to be the desired "mileage" speed for both.