05-06-13, 09:29 PM
To meet type approval, the speedo on a vehicle must be between +10-0%. In other words, it can over read by up to 10% but cannot under read at all. This allows for the increase in displayed speed as your tyres wear down and the rolling circumference reduces, so it will be more accurate on new tyres than almost worn out ones.
As for middle lane hoggers, it isn't only middle lane. I live near the 4 lane wide stretch of A1(M) near Peterborough and drive it every day. At least 3 times a week you find one person sticking in lane 3 with little or no traffic in lanes 1 and 2. I put it down to the slow lane, medium lane, fast lane mentality. I'm doing 70 (but is only doing 65 in reality due to the speedo error) so I need to be in one of the faster lanes, not the slow lane.
As for middle lane hoggers, it isn't only middle lane. I live near the 4 lane wide stretch of A1(M) near Peterborough and drive it every day. At least 3 times a week you find one person sticking in lane 3 with little or no traffic in lanes 1 and 2. I put it down to the slow lane, medium lane, fast lane mentality. I'm doing 70 (but is only doing 65 in reality due to the speedo error) so I need to be in one of the faster lanes, not the slow lane.