what's on here? a question?
last time i had 155/70/13 (547mm total diameter) the speedo read way too high. at 70mph gps speed it read 75-76mph. currently i'm on 195/50/15 (576mm total diameter) and the speedo is bang on target.
speedometer and odometer are both connected so yeah changing tyre diameter affects the speed reading and odometer as well as gearing, economy, handling, noise, comfort, wheel durability etc