No its the fact that our miles are metricThe Bridgestone Battalax Bt45 v rated come in stock sizes. A popular value in bias ply when having to buy two sets but my 110/80 reads 80mph at a GPS 75. Ms B's speedo is an indicated 80 with a GPS 76.
Perhaps it's a British thing as her '09 Mini is off by +5 mph too.![]()