Speeding through average speed camera zones - What gives?

[ashleyman]

My friend got caught at the average speed cameras when they were widening the M23 southbound.

It was his first time that anything has come from his speeding. I don't know what speed he was doing at the time but he went on a speed awareness course. It wasn't the first time he'd been through that section of road as he was doing it every weekend for about a month before the ticket came through.

I personally tend to stick to my speedo's 50 which means I'm overtaken by everything from Nissan Micras to huge lorries. Now learning that they're measured purposefully slow would explain why some of other vehicles I've been have sailed through 40MPH speed cameras at 45-48 and never been flashed.

I guess I have some space to speed up a bit!

[Vocht]

I use the M60 pretty much everyday which has had 50mph average speed cameras 'live' for the past few months now. I've always used the 10% + speedo inaccuracy theory so set my cruise control to 56mph and have never had any problems.

[sicasey]

So why do modern speedometers err on the side of caution?

Is this the same for Merc / Audi style digital screen readouts?

Shirley they should be bang on accurate.

[austinsmirk]

I know 3 people so far who have been done by those cameras.

so its 51mph for me on the cruise.

but no, I don't get people whacking through them either, other than to assume the car is hookey.

[romeogolf]

Another point is that some regulars know where the cameras are. So if they know they've gone past the last camera of the section, they'll speed up. Or if they're not at the first one yet, even if the signs have started, they'll be travelling quicker.

[KTF]

sicasey said:

So why do modern speedometers err on the side of caution?

Calibration costs money.

[sicasey]

KTF said:

Calibration costs money.

That cant't be the reason.

[xRIEx]

sicasey said:

So why do modern speedometers err on the side of caution?

Is this the same for Merc / Audi style digital screen readouts?

Shirley they should be bang on accurate.

I can't remember which regs, either Construction & Use or type approval (possibly both) allow a speedo to overread by up to 10%, but may not underread at all. It's better to have a couple of mph on the "safe" side than getting a massive legal hammering.

The more recent cars I've semi-scientifically checked have tended to overread by a (seemingly) %age variation up to about 40mph, then (approximately) consistently display 3-4mph higher than a GPS reading up to 70 (and no doubt beyond ) - this makes me think that a modern speedo is as accurate as they want it to be.

[irfan1712]

i got caught for the first time ever three weeks ago on the M4 Port Talbot average cameras. 56 in a 50, luckily had the option of a speed awareness course. no idea why i was doing 56 i was probably in a world of my own or foolishly thought it was a 60.

for the average speed cameras linked to the matrix signs above the motorway, dont these motorway signs need to be displaying the speed for the cameras to be working?

an example are the average cameras on the M4 around Newport. if the matrix signs dont display the speed how does one know what the limit is in that area as there are no fixed signs if memory serves me right? (genuine question, not being sarcastic!)

[xRIEx]

irfan1712 said:

for the average speed cameras linked to the matrix signs above the motorway, dont these motorway signs need to be displaying the speed for the cameras to be working?

I don't think they are average speed cameras; the boxes behind the signs look remarkably like gatsos.

[TeaNoSugar]

aero93 said:

Does anyone know anyone that has actually been caught by these?

A colleague of mine was caught on the section between J28 and J25 of the M1 while the widening and new gantries were going in a few years ago. He was recorded averaging just over 60mph as far as I remember.

I drive from J34-J26 and back 3 days a week. Speed limiter always set to 57mph. Thats fast enough to keep me out of the way of the HGVs, and in the last 3 years while those works have been ongoing I haven't had a ticket. I wouldn't want to risk any more, but do see the odd car barrelling through overtaking everything else, I just assume they're not legit and don't give a f***.

On a related note, does anyone know exactly why all the new "Extrudakerb" central barriers were ripped out a few months back after only being in place for a year or so??

EDIT: I'm thinking of the yellow cameras in the roadworks, not the smart-motorway gantries (they're not average speed cameras are they?)
Also, on the M1 near J27 there are some new cameras which are cantilevered off the outside of the new gantries, so overhanging beyond the hard shoulder. Are they a new speed camera as well, or something else entirely??

Edited by TeaNoSugar on Thursday 11th February 12:09

[Bonefish Blues]

romeogolf said:

Another point is that some regulars know where the cameras are. So if they know they've gone past the last camera of the section, they'll speed up. Or if they're not at the first one yet, even if the signs have started, they'll be travelling quicker.

Yep, not all cameras are equal either, in the sense that only some are active - tend to be the ones which have carriageway illumination at night, in addition to carriageway markings (letters and numbers) I believe.

[sicasey]

xRIEx said:

I don't think they are average speed cameras; the boxes behind the signs look remarkably like gatsos.

Are they infarct only enabled when the reduced speed is illuminated?

[xRIEx]

sicasey said:

xRIEx said:

I don't think they are average speed cameras; the boxes behind the signs look remarkably like gatsos.

Are they infarct only enabled when the reduced speed is illuminated?

I've heard claims that they will trigger at 90 even when not illuminated - I've not tested that myself, but I have been travelling at, ahem, something over 70mph and had people passing me under the gantries and still no flash; I would estimate that 85 on the clock (depending on car) wouldn't trigger anything, even if they are active in those situations.

[sicasey]

xRIEx said:

I've heard claims that they will trigger at 90 even when not illuminated - I've not tested that myself, but I have been travelling at, ahem, something over 70mph and had people passing me under the gantries and still no flash; I would estimate that 85 on the clock (depending on car) wouldn't trigger anything, even if they are active in those situations.

I love all of these urban myths, proper pub talk

[Adam Ansel]

irfan1712 said:

i got caught for the first time ever three weeks ago on the M4 Port Talbot average cameras. 56 in a 50, luckily had the option of a speed awareness course. no idea why i was doing 56 i was probably in a world of my own or foolishly thought it was a 60.

for the average speed cameras linked to the matrix signs above the motorway, dont these motorway signs need to be displaying the speed for the cameras to be working?

an example are the average cameras on the M4 around Newport. if the matrix signs dont display the speed how does one know what the limit is in that area as there are no fixed signs if memory serves me right? (genuine question, not being sarcastic!)

But you weren't doing 56. They have deducted 10% + 2mph from the charge. So you were in the mid 60s.

[Bonefish Blues]

Adam Ansel said:

irfan1712 said:

i got caught for the first time ever three weeks ago on the M4 Port Talbot average cameras. 56 in a 50, luckily had the option of a speed awareness course. no idea why i was doing 56 i was probably in a world of my own or foolishly thought it was a 60.

for the average speed cameras linked to the matrix signs above the motorway, dont these motorway signs need to be displaying the speed for the cameras to be working?

an example are the average cameras on the M4 around Newport. if the matrix signs dont display the speed how does one know what the limit is in that area as there are no fixed signs if memory serves me right? (genuine question, not being sarcastic!)

But you weren't doing 56. They have deducted 10% + 2mph from the charge. So you were in the mid 60s.

I tghink your muddling this up with the ACPO Guidelines, aren't you. The speed will be accurate.

[theboss]

w1ntermut3 said:

Not a huge amount to add to the discussion, as both 10% rules and speedo innacuracy have been covered.

A final point worth considering: take your 55-60mph cruise control driver, skirting the limit. He will at some point encounter a bimbo box overtaking another at 45mph. This will then give him some time at 60+ before his average speed breaks the magic 50+10%+2+error.

In reality this happens about once every two minutes on a road like the a1. Hence, blokes doing 70. Because actually, theyre still averaging like 49.

Exactly this. I'm traversing the two specs installations on the M5 between Gloucester and Almondsbury on a regular basis and tend to stick it at an indicated 60 knowing that I'll be bimbling along at 43mph for at least some of the stretch.

I had my first 'specs rage' incident this week; a van driver went mad as I crept past in L2 and got on the horn, waving his hand with 5 fingers raise (50?) whilst practically foaming at the mouth. Quite bizarre.

[xRIEx]

sicasey said:

xRIEx said:

I've heard claims that they will trigger at 90 even when not illuminated - I've not tested that myself, but I have been travelling at, ahem, something over 70mph and had people passing me under the gantries and still no flash; I would estimate that 85 on the clock (depending on car) wouldn't trigger anything, even if they are active in those situations.

I love all of these urban myths, proper pub talk

It all needs to be taken with a pinch of salt. I'm sceptical of most things I here unless it can be verified. It's just a case of personal responsibility, because "well my mate said ..." doesn't hold up in court.

[Pesty]

TeaNoSugar said:

A colleague of mine was caught on the section between J28 and J25 of the M1 while the widening and new gantries were going in a few years ago. He was recorded averaging just over 60mph as far as I remember.

I drive from J34-J26 and back 3 days a week. Speed limiter always set to 57mph. Thats fast enough to keep me out of the way of the HGVs, and in the last 3 years while those works have been ongoing I haven't had a ticket. I wouldn't want to risk any more, but do see the odd car barrelling through overtaking everything else, I just assume they're not legit and don't give a f***.

On a related note, does anyone know exactly why all the new "Extrudakerb" central barriers were ripped out a few months back after only being in place for a year or so??

EDIT: I'm thinking of the yellow cameras in the roadworks, not the smart-motorway gantries (they're not average speed cameras are they?)
Also, on the M1 near J27 there are some new cameras which are cantilevered off the outside of the new gantries, so overhanging beyond the hard shoulder. Are they a new speed camera as well, or something else entirely??

Edited by TeaNoSugar on Thursday 11th February 12:09

Im up and den the m1 and 62 all the time. Also other roads with average cameras all the time. I drive about 30k miles a year for work. How I haven't been done by these or in the dash camera thread I have no idea. I set the cruise at around 54 which is about 50-51. What my specific issue is if they are long enough like the fking m1 has been for years after miles and all of a sudden the road opens up I automatically just floor it forgetting I'm in an average zone. Then drive for miles and remember them think oh fk. So if you see a dick driving like he stole it it's probably me. No tickets yet.