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multiraider2 wrote: ↑Sun Oct 29, 2023 13:34
I always find that if I set 50 on the cruise control through lengthy roadworks, I tend to be very slightly overtaking vehicles. Given that 50 indicated is likely to be 49 or 48, there is a degree of excess caution being exercised by most and I suppose actually me. I won't hold people up though.
exactly
alsoway interesting to compare *none calibrated* car speedo to GPS or if you have a measured mile to hand to the measured mile
I see a logo on ASCs near the yellow vultures. I am curious if a company does all the processing or if the system is leased/owned to the local county. Just interested in who gets to see the number plate info through the NIP process. Would be funny (not) if it was an offshore outfit
Unrelated, the new models also seem more compact or hidden like on the M4 elevated. The older ones seem to have a light stalk type thing next to them like the A38 Weeford.
My car sat nav shows average speed cameras and shows the average speed being maintained between any two. I also have a phone app that does the same thing. The phone app is more accurate as it bases speed on GPS whereas the car sat nav uses the car speedo which is 3-4 mph fast. I also have a mini GPS speedo permanently installed. Very handy on my continental trips as it converts to km/h with two clicks.https://tinyurl.com/z7vjrxf3
multiraider2 wrote: ↑Sun Oct 29, 2023 13:34
I always find that if I set 50 on the cruise control through lengthy roadworks, I tend to be very slightly overtaking vehicles. Given that 50 indicated is likely to be 49 or 48, there is a degree of excess caution being exercised by most and I suppose actually me. I won't hold people up though.
exactly
alsoway interesting to compare *none calibrated* car speedo to GPS or if you have a measured mile to hand to the measured mile
Trials showed that fatigue of driving through works, while not an immediate risk if Chapter 8 compliant, tended generated some undesirable behaviours for works longer than 6km. This includes a much greater variation in speeds. This will mean more chance of encountering traffic doing 45 mph or less (either actual or indicated).
How accurate are those displays by the road displaying your speed as you go past?
When I'm doing 30 on the speedo they usually show 28, suggesting my speedo is the usual bit fast, giving me confidence to do 55 in a 50 average speed area without being anywhere near the cutoff point.
My speedo is similar. A 30 mph reading on the speedo always shows as 28 mph on roadside speed indicators. This is how it should be, IMHO. What I'd like to know is, it is a percentage over-read, or just 2 mph for any speedometer reading. So I've got 75 on the speedo on the motorway, it would be about 70 actual speed if it's a percentage, or are my maths useless ?
fras wrote: ↑Mon Mar 04, 2024 16:48
My speedo is similar. A 30 mph reading on the speedo always shows as 28 mph on roadside speed indicators. This is how it should be, IMHO. What I'd like to know is, it is a percentage over-read, or just 2 mph for any speedometer reading. So I've got 75 on the speedo on the motorway, it would be about 70 actual speed if it's a percentage, or are my maths useless ?
Just use Google Maps as a satnav on a route with different speed limits - it'll show your GPS speed - every car model is different but my VW Touareg's speedo consistently reads 1 mph over GPS speed from 30-70 mph - it is though fitted with oversize tyres which are 2.0% bigger than original.
