Joe Boatman
Established Member
At 31 mph in my 2021 MG5, the nearest grinning radar speed sign displays 30 mph!
Although most of my previous cars exaggerate speed up to 8% the distance has always been much closer, unless I've changed tire profile.Worth noting that the MG4's efficiency is better than some competitors simply due to the fact that some competing cars over-read significantly which exaggerates mi/kWh.
That's interesting. I have never measured distance independently, I assumed it was always driven by the speedo. How do these cars get one right but not the other?Although most of my previous cars exaggerate speed up to 8% the distance has always been much closer, unless I've changed tire profile.
That's my assumption. Here the rules are, "mustn't be over but can be 8% under".I am assuming that they deliberately overread the speed but not the distance?
So is that 8% just for mileage recording?, as with speed shown, they're not allowed to under read at all, but can over-read by up to 10% plus 6.25 mph in the UKThat's my assumption. Here the rules are, "mustn't be over but can be 8% under".
Both fed from the gearbox take off, but to be on the safe side, the speedo is calibrated to overread.
That would put you at nearly 40 in a 30.... can over-read by up to 10% plus 6.25 mph in the UK
No, you've mis-understood! We are talking about "over reading" speedometers, so it's showing more than what you're travelling at, not less! So at the maximum allowable error, you'd be travelling at around 22mph whilst the car would be showing 30mph.That would put you at nearly 40 in a 30.
If you're talking about the speed at which you can get prosecuted, the NPCC (was ACPO) guidelines (which most forces follow) is 10% + 2mph.
I understood recently that some forces don't follow those guidelines religiously and some even sometimes use zero tolerance. But most still follow the guidance apparently.