Don’t know if this has been done before but just wondered if they did?
I travelled from Hebden Bridge to Kent down the M1 and M25 and when in the 50mph average speed camera zones people were travelling faster than 50mph.
Anybody been done in an average speed zone?

But were they averaging more than 50mph?

A lot of folk travel at 55 indicated reckoning they’re doing around 50 in reality. They’ll then stick another 5 onto that to do 60, reckoning they’ll only be doing 55 and that the cameras will be set to trigger a letter at 60.

AFAIK, they do work. There was an article on the local Beeb website (I’ll try and dig it out) when they added ASCs to the M5 past Brizzle when installing the managed motorway section saying how many thousand drivers had been caught.

In terms of working though, they’re the only thing that have allowed heavier loads of traffic through 50mph roadworks before tailbacks. A darn site better than the Gatsos used previously.

I haven’t been caught, but I know several people who have.
So yes.
edit.. The ones that used to be on the M1 earnt millions iirc.

I was doing dot on 50mph.
I have had a clean licence since 1992 when i started driving. God knows how!
I have never heard of anybody being done hence the question

The temporary average speed ones definitely work and the fixed variable ones that are now popping up are also left turned “on” even when the gantry signs are off – there’s an article about this on the Beeb website.

I still chuckle at the morons who brake heavily from 60mph when they see the cameras as if it will make a difference. Clearly they skipped the stats class in GCSE maths.

everything’s been done before
On roads I use, these things are massively effective – to the point where we’re all forced to do 40 in a 50 because some arse doesn’t understand what’s going on and also can’t bring themself to get out of the outside lane to let other cars past

http://news.bbc.co.uk/1/hi/england/cumbria/8559670.stm

They do work so be careful.
However due to a legal mixup on the M25 ( not the 50mph zone near Clakett Services) but Kent/Surrey area they are not switched on. Something to do with which legal framework has jurisdiction. . They’ve been off for 2 years or so now.
Freely available knowledge that if you want to search for it yourselves.

They do but there is a story that they only work if you’re in the same lane when you pass the second camera as you were when you passed the first. When this circulated up here the cops roundly condemned this type of irresponsible behaviour but never said yes or no to whether this true or not.

Assuming they are completely ineffective against motorbikes? As they are heads up cameras?

most car speedos will overread by 10% so 50mph actual == 55mph on your speedo. The cameras will have a tolerance level built in, say 5mph so probably 60mph or so on your car speedo.

I thought both the lane change issue and the legality of the font used on the led signs had both been resolved and the m25 cameras were now working?

A colleague’s 9 points confirm the M25 Kent/Surrey road works ones are active.

Yes! Twice on the 40mph stretch of the M50.

@soops I was going to start a thread on exactly the same question !

FYI my GPS shows car speedo under-reads by about 7%, so add a bit of a margin which police/cameras use (ie you don’t get knicked for doing 51 in a 50) and you can be pretty sure you’re safe at 10-12% over the limit, then add in the averaging effect and I think that explains why you have to be going pretty fast to get knicked by the averaging cameras. I believe their primary purpose is to check road tax and insurance, could be wrong about this.

Assuming they are completely ineffective against motorbikes? As they are heads up cameras?

On the M25 Kent section they scan both the front plates and the rear plates. I have no idea if it’s enough to clock motorbikes but I wouldn’t risk it. The ordinary traffic cameras would pick up a motorcyclist taking the piss and overtaking everyone, I don’t think it would be very hard to prove that they hadn’t complied with the legal speed limit.

Don’t think they’re working on the managed section from 20-15 on the M25. Average speed in lane 3 when the cameras are showing 50 is easily in excess of 70.

Wait… Do you mean the roadworks average speed ones or the gantry cameras? Roadworks (SPECS) definitely work as my sister’s 6 points testify to. Gantry ones turned off.

The permanent average speed ones on the M60 work, I got done last month doing 60 when it was a 50 limit because I am obviously stupid!

Answer yes.

Do you mean the roadworks average speed ones or the gantry cameras?

I’m talking about the average speed cameras in the roadworks of the 10 mile section of the Kent M25, they point both to the front and the back of vehicles.

The permanent average speed ones on the M60 work, I got done last month doing 60 when it was a 50 limit because I am obviously stupid!

The ones at J25 going clockwise? Yes, they work – a work colleague got done there.

Never sure how much of this is urban myth – all the comments about speedos always over-reading by 10% and you also get people saying that avg spd cameras don’t work if you change lane between camera gantries.

Looking at my speedo vs my sat nav there’s never more than about 4mph between them which is about 5% at 70mph and at lower speeds they’re almost identical – any discrepancy I’ll usually put down to the sat nav being rubbish rather than the speedo.

Yes, J25 clockwise. I can’t even do the speed awareness course as I did one 2 1/2 years ago, what a dick!

I’m new to this forum, can someone please tell me how to quote another poster.

Never sure how much of this is urban myth – all the comments about speedos always over-reading

It’s illegal for a speedometer to under-read, so most if not all will over-read to err on the side of caution. How much by is another matter.

I was surprised on my way to London on Saturday night. The gantry cameras on the north bound lane we happily flashing away at speeders despite there being no temporary speed limit in place. I didn’t think those ones were ever on. I made sure I was under the speed limit on the way home later that night.

Over head gantry ones work on the M42, have seen then flashing cars (reduced speed limit in place at time)

speedo’s on cars are usually up to 10% out so I’ve read that 10% is allowed. This might help explain why cars come past or go slow in these zones as everybody might think they are doing 50 but everybodies 50 is different. Then there are the knobs who either dont understand the word average or are just knobs.

does naybody think the law to keep drivers left has worked? I see no difference with drivers still overtaking a car a mile away in the middle lane. My pet hate.

To answer the OP, Yes. I have three points that can testify to that.

I think the variable speed limit ones must have a larger margin for error[i]going over the limit[/i] than normal speed cameras.

Going past Birmingham on the M40-M42 I went through the slip roads in a 60, then realised at the last second that the next sign was a 50 so definately went through at a (Sat-Nav) 60.

So either:
*I got lucky and the camera didn’t pick me up.
*There’s more than the usual 10% +3mph margin
*They allow you to go through the first sign over the speed limit then slow down for the next gantry

Also what’s the legality of the sign just changing as you go through, presumably there must be a delay between the sign flashing 50 and the cameras being activated, otherwise the first 10 cars would always get caught!

In answer to the op I think they work out the Average Speed.
What possible reason would you have to believe they did not work?

There was a FOI request on the ones on the M27 which showed the tolerance was set very high, the proportion of people caught was minute. That was a good few years ago now, I imagine they’ve made them more stringent now.

My sat nav reckons I’m doing 50mph when my speedo is reading 55mph, I generally go about 59mph (speedo) through the 50mph M4/M5 zones near Bristol. Pretty sure they don’t kick in until at least 60mph actual though as a couple of times I’ve gone through at least one pair doing over 65mph (indicated) and not received a ticket. And yeah if there are actually people working I’ll drop down to 50mph, for months though the M4/M5 Bristol ones were in a ‘testing & calibration’ mode with all three lanes open and no one working so frankly they can **** off.

They also measure your speed between random cameras too don’t they? So between camera 1 and 3 and 2 and 7 for example, so speeding through the first few and slowing right down for the remainder to average 50mph is likely to get you nicked. Also stops people hiding behind lorries.

and they arent always on, so maybe some of you were lucky.

when they are on, they usually put on a random two and measure between them, could be number 2 and 7 or 5 and 8, random. so again if you’ve gone through over the limit, maybe you were lucky.

I always assumed they were a form of modern Panopticon.

I did my M25 (south, Kent/Surrey, A3, return) route over the weekend and even in the Clackett Service are roadworks there were cars zipping by me, some I’m sure got clicked and makes me wonder how they will travel next week when they are banned.. 😆

Thanks for the M25 Gantry cameras info, thought the legal issue was still o/s hence the number of “plod cars” sitting on the hard shoulder.

Hey ho.. Better tell my Motorbikermate.

The ones that were on the M1 from M25 to Luton for years definitely could not track you switching lanes.
I had a clean license and was travelling up and down here every week at silly hours, so I decided to risk 3 points to see if they worked.

I can safely say, that even enough over the NSL to definitely trigger something, I never got anything through the post.

A14 Huntingdon to Cambridge – Yes definitely.