Quote:
Originally Posted by Number4
It is completely true. I have never driven a car that does not do this.
If you have a GPS, compare the GPS speed to the speedometer.
Your GPS should be 99.99% accurately describing your speed, unless it is a dud.
The speedometer will most likely be over reporting by 10%.
The law requires speedometers to be accurate to +/- 10%. Most manufacturers err on the side of caution.
The old bill can't book you if you are within this speed range. eg 77mph is just ok on a dual carriageway.
Changing wheel and tyre size will effect your gearing and the speedometer reading. |
I suggest that you consult a lawyer if you believe that you will not be prosecuted if you exceed the national speed limits by 10%. The police may use their discretion to not report you for the offence, but they may also choose not to do so.
And speed cameras are now being set to as low as 1 mph over the limit at certain points, at which you will receive a speeding ticket. It's a good money raising programme, and more areas are lowering the "discretion speed".