When I go to work in car on the m62 j30 speed cameras 50 mph but trucks pass me on the limiter,are risking it,keith
Your car speedo is not as accurate as the truck’s tacho.
Ha get the point,i am all so a tacho fitter 
keith
If you want to know your actual speed then use a sat-nav.
I set my cruise at 81 kph, the sat nav confirms the speed at 50 mph, so I’m always overtaking cars that seem to be doing 47/48 mph.
The law says 50 mph, so I try to stick to the law & not my speedo.
In virtually everything I’ve driven recently (car, van, truck whatever) when the vehicle speedo says 50 the sat nav says 47 or 48!
alamcculloch:
If you want to know your actual speed then use a sat-nav.
I think all that gives u is your ‘GPS speed’ not your actual speed, it’s hard to work out an exact speed hence the tolerances.
I set my limiter to 83 because I’m a rebel.
alamcculloch:
If you want to know your actual speed then use a sat-nav.
try that in the Dartford tunnel 
the Axors I drive regularly all read 56 on the limiter but range from 53-58 true speed quite happy to get a plodder on the A road trunks but prefer the flyers on the motorways
Dafman:
I set my limiter to 83 because I’m a rebel.
+1
chicane:
the Axors I drive regularly all read 56 on the limiter but range from 53-58 true speed
Mine says 56 but Nav says I am doing 57. When empty I seem to fly past many trucks with nothing hardly overtaking me but is it just me that the new Volvos are quick?