Radar speed signs

iguana

How accurate are the radar speed signs that are at the side of many roads? I've noticed that they nearly always tell me I'm going faster than my speedometer is telling me I'm going at. It's making me very paranoid that my speedometer is incorrect and I'm unwittingly speeding when I think I'm driving at/near the limit. I usually match my speed to the traffic I'm in, unless the cars in front are speeding, and usually we seem to be driving bang on the speed limit according to my speedometer. I'm going to get someone to sit with me and check my speeds on their phone. But until I get a chance to do that should I aim to drive below what my speedometer is saying?

Wanderer78

Similar experience, mines nearly always out compared to them. I'd like to think they're more accurate than mine, but who knows. Doesn't bother me too much

XsApollo

Depends how the speedo is set.
They are pretty accurate to what my A6 says.
But the Saab I had before they were a good 7 to 8km lower.

biko

Drive with a sat nav app running, it should give you an accurate reading.

bazz26

Speedometers are always calibrated to run a little over intentionally by manufacturers. GPS is the most accurate form of measurement.

Del2005

I've started ignoring them since they showed me red when doing 50 in a 50 zone, had cruise control set to 50. If they can't even get the basics correct I don't bother with them.

But of course they are going to over show your speed. They are from the RSA and we all know that it's only exceeding the posted limit that kills!!

HeidiHeidi

Del2005 wrote: »

I've started ignoring them since they showed me red when doing 50 in a 50 zone, had cruise control set to 50. If they can't even get the basics correct I don't bother with them.

But of course they are going to over show your speed. They are from the RSA and we all know that it's only exceeding the posted limit that kills!!

I passed two today that showed flashing red when I was doing 50ish in a 60 zone!

SmartinMartin

HeidiHeidi wrote: »

I passed two today that showed flashing red when I was doing 50ish in a 60 zone!

They were warning you to go back to the mountain, Grandfather's ill.

grogi

iguana wrote: »

How accurate are the radar speed signs that are at the side of many roads?

They are typically pretty accurate.

I've noticed that they nearly always tell me I'm going faster than my speedometer is telling me I'm going at.

That would be extremely rare, typically it is the other way round. Are you driving on stock tires?


As advised, measure your speed with a GPS, exp. a phone. Those are very precise. Go to an empty motorway, set a cruise control to 50, 80, 100 and 120 km/h and see what it really is.

HeidiHeidi

SmartinMartin wrote: »

They were warning you to go back to the mountain, Grandfather's ill.

_Kaiser_

HeidiHeidi wrote: »

I passed two today that showed flashing red when I was doing 50ish in a 60 zone!

I regularly pass one like that which complains about doing 50-60 in a 60 zone.

It's actually accurate vs the digital display in my A6 though