Hi

My speedo runs at about 10% more than my actual (GPS) speed. Example, 70mph on Speedo is 63mph. 100mph on Speedo is 90mph. 45 on Speedo is 41mph etc.

Does anyone else have this issue and is there a way to finer tune the speedo to match?

My friends Fiesta only runs about 2% ahead and it's starting to bug me.

Cheers

Perfectly normal, all like it for safety, and not much you can do about it really. Don't have the handbook at hand ( ) but it's noted as a safety feature in there.

10% is a lot though! Is there nothing that can be done to bring it back a little?

You can get them calibrated but its expensive.

All our police cars used to have them but these days its only traffic cars that have them fitted due to cost

Every car I've ever checked by GPS has over-read by around 10% (non Fiat too). It will alter slightly based on tyre wear/pressures, but the biggest change is when fitting a larger wheel/tyre combo that affects the rolling radius.