"Smart" Motorway Speed Question

[LeMarchand]

There is a stretch on a local motorway where work has been ongoing for a while and it has metal temporary speed limit start/end signs. However, the overhead signage never seems to back this up. The site manager claims this is because the overheads only kick in when work is actually in progress (normally overnight) and it is permitted to ignore the temporary signs, but I can't find anything to confirm this. Anyone got a reliable source?

 

Also, why do so many people drive well under the speed limit in lanes 2 and 3 when it is both safe to drive at the speed limit and the lanes to the left are clear? This wasn't so noticeable when it was a three-lane motorway!

[Andrew_C]

If the "temporary" signs are red circle type, as a normal speed limit, I'd not trust anyone saying you can ignore them.

 

Second point - idiots.

[Chuckster]

Whether the smart motorway signage is lit up or not I adopt the following rule: Signage speed + 10% + 2.

 

I apply the same rule when driving through a stretch where there are roadworks and the signage displayed is average 50mph.

[Andrew_C]

Whether the smart motorway signage is lit up or not I adopt the following rule: Signage speed + 10% + 2.

I have read that the camera's on "smart" motorways are set a LOT closer to posted speed than plod at the side of the road. I'd be wary...

[Davit2005]

Same here, you can't rely on the 10% plus 2mph rule. Some forces might not use that formulae.

[nicholab]

I have read that the camera's on "smart" motorways are set a LOT closer to posted speed than plod at the side of the road. I'd be wary...

 

When I was at the traffic control centre in Belfast for a talk they said that new Home office approved camera would be rolling out soon that will take a picture of your car and the speed limit sign.

 

I would always follow the speed limit if yellow camera are in place unless the sign says camera not in use under them. The lower speed limit is to help protect workers so it quite nice if you follow it.

 

I would also follow the speed limit in Wales as they also seem to have a very extensive speed camera network.

 

I not suggesting breaking the normal national speed limit at any point. It is now like play some kind of horrible computer game with certain speed limits. I heard of someone getting a ticket at 22mph! I did not believe 20mph was enforced.

Edited May 23, 2023 by nicholab

[Chuckster]

I have read that the camera's on "smart" motorways are set a LOT closer to posted speed than plod at the side of the road. I'd be wary...

 

Same here, you can't rely on the 10% plus 2mph rule. Some forces might not use that formulae.

 

I would do 57mph when there were roadworks between Rugby and Milton Keynes a few years back and quite recently up until when the roadworks finished on the M6 between juntions 13-19.

[Dos_Box]

Not sure about the accuracy of the cameras, but I did have my first experience of smart motorways on the way to/from BETT this year.

Due to the rail strikes I had to drive down and leave the car in a nearby car park for the week. On the way back (it was the Saturday at the start of the Easter hols), the M1 and some sections of the M6 were under controlled speed limits almost all the way to Cheshire (for the parts converted to smart motorways). To my surprise, it did keep the traffic flowing and not once did we get stuck in a jam, despite the high traffic levels. I did see several cars broken down on the inside lane, but the signage did give plenty of warning to change lanes. I can see someone crashing into one of these eventually though!

Edited May 24, 2023 by Dos_Box

[PotNoodleTech]

If it's a speed limit encased in a red circle then it is a legal limit no matter if it's a physical sign or a bunch of LEDs on a gantry.

 

If there are no 50 red circle signs at all in the area, led or physical then the speed limit would be national speed limit 70 for a car.

 

If it's in a yellow triangle or anything else then it's not a legal speed limit just a suggestion.

[CHiLL]

I'd be going off what the sign in the red circle says, as that should override the normally stated speed limit.

 

For exmaple, if you're driving down a non-smart motorway or a dual carriage way, you'll have the white circle with a black line sign saying it's national speed limit. When that road has road works, they don't remove those national speed limit signs...but they place those speed limit in red circle signs, which override the existing signage.

[LeMarchand]

I'd be going off what the sign in the red circle says, as that should override the normally stated speed limit.

 

For exmaple, if you're driving down a non-smart motorway or a dual carriage way, you'll have the white circle with a black line sign saying it's national speed limit. When that road has road works, they don't remove those national speed limit signs...but they place those speed limit in red circle signs, which override the existing signage.

 

Good point. You'd think they'd sync the overheads, though. It's a couple of minutes*, if that, work.

 

*I assume.

[MartinT]

My speedo is spot-on with GPS speed (since I changed wheels/tyres a while ago). I cruise control at 75 on most motorways and sail past the cameras on the long M3 smart motorway stretch. I won't risk any faster. If the posted speed goes lower, so do I as they sync to the prevailing speed limit.

[MartinT]

I heard of someone getting a ticket at 22mph! I did not believe 20mph was enforced.

 

The road outside our school is speed humped and 20 limit. The Police have more than once been waiting near the end of the road with hair dryers checking all the speeds. Plonkers*. It's hard to do 20 in a higher gear than 2nd.

 

* I say this as the serious crime clear-up rate continues to fall. For crying out loud, deploy them to solve real crime!

[HarryMonkey]

When I did a speed awareness course a similar question came up and the answer from the course leader was that you must always drive at the lower speed limit regardless.

 

Just as an aside, I read that the cameras that they use in the roadside police vans have a range of 1000 metres ... approx 2/3 of a mile so the chances are, by the time you spot the camera van and slow down, it's too late.

[CHiLL]

Good point. You'd think they'd sync the overheads, though. It's a couple of minutes*, if that, work.

 

*I assume.

Yeah, I've noticed quite often that there can be sync issues between gantries or specified speeds limits for what appears to be no apparent reason. Being in Birmingham, I have to deal with smart motorways if I want to go anywhere outside of Birmingham and the trip up the M6 to see family in Liverpool is almost all smart motorway. People don't understand that you basically don't use the hard shoulder unless it states you can (usually with writing or a speed limit posted for that lane). The main issue with them is if you break down in an active hard shoulder and can't make it to a refuge point, leaving you stranded. That's an active lane until the highways agency are made aware of your stranded vehicle.

 

Just as an aside, I read that the cameras that they use in the roadside police vans have a range of 1000 metres ... approx 2/3 of a mile so the chances are, by the time you spot the camera van and slow down, it's too late.

This is correct.

[mikeprice]

I would suggest that the last sign that you passed is the pne that is legally valid

 

so if you pass a 50 sign made of metal - but then the overhead sign says 60 - then you can do 60

 

however, if you get a speeding ticket for doing 60 then I have no idea how you could prove that the last sign you proved said 60 when the traffic people can easily find paperwork that shows that the road was dropped to 50 due to the roadworks

 

So I would stick to the road work signs unless the overhead ones are lower

 

You would thing that they would be synced - but who knows how well designed their computer system is??

[CHiLL]

I would suggest that the last sign that you passed is the pne that is legally valid

 

so if you pass a 50 sign made of metal - but then the overhead sign says 60 - then you can do 60

 

however, if you get a speeding ticket for doing 60 then I have no idea how you could prove that the last sign you proved said 60 when the traffic people can easily find paperwork that shows that the road was dropped to 50 due to the roadworks

 

So I would stick to the road work signs unless the overhead ones are lower

 

You would thing that they would be synced - but who knows how well designed their computer system is??

I think even if you have a dashcam and can prove that both signs were present and conflicting, you'd still get done as the temporary roadworks speed limit should have priority.

[RedwayNetworks_Michael]

I think even if you have a dashcam and can prove that both signs were present and conflicting, you'd still get done as the temporary roadworks speed limit should have priority.

 

i would agree with this, the response would be if you wasnt sure of the limit you should have chosen the lower limit.

[LeMarchand]

Thanks for the clarifications, folks.

 

Just to make my position clear: I would like to drive at the speed limit where it is safe to do so, but this stretch seems to be ignored by most drivers. It's particularly frustrating on my way to work as you would have to fight your way out to lane 3 or 4 to get past people driving at 60 in lanes 1 and 2, and then get back to lane 1 unless you want someone trying to kiss your rear bumper for you having the temerity to slow down to the displayed speed limit. I normally just stay in lane 1 as it's less stressful, even though it's slower.

[RedwayNetworks_Michael]

Thanks for the clarifications, folks.

 

Just to make my position clear: I would like to drive at the speed limit where it is safe to do so, but this stretch seems to be ignored by most drivers. It's particularly frustrating on my way to work as you would have to fight your way out to lane 3 or 4 to get past people driving at 60 in lanes 1 and 2, and then get back to lane 1 unless you want someone trying to kiss your rear bumper for you having the temerity to slow down to the displayed speed limit. I normally just stay in lane 1 as it's less stressful, even though it's slower.

 

sadly this is down to lazy drivers in my opinion not considering others and basically hogging lanes.

Lane 1 and 2 i usually find faster as no traffic in them. Lane 3 and 4 has traffic due to hoggers.

 

Its crazy the amount of drivers that hog lanes

[CHiLL]

sadly this is down to lazy drivers in my opinion not considering others and basically hogging lanes.

Lane 1 and 2 i usually find faster as no traffic in them. Lane 3 and 4 has traffic due to hoggers.

 

Its crazy the amount of drivers that hog lanes

I also often find that moving to lane 1 when you approach very slow traffic, especially coming up to junctions or an accident is actually faster, as you have a lot of people trying to go lane 3.

[Davit2005]

We are quite bad in this country, it might be down to people thinking them as slow lanes or jus for lorries.

 

You should be in lane one unless you are overtaking, sometimes I will move to lane two if I see a busy on ramp and it is safe to do so and traffic allows. The other camp of car drivers that won't go into the outside lane even if they have to slow down and sit up the rear of another car, it is like they feel they are more important to be in lane one but not important enough to be in lane three :-)

[RedwayNetworks_Michael]

I also often find that moving to lane 1 when you approach very slow traffic, especially coming up to junctions or an accident is actually faster, as you have a lot of people trying to go lane 3.

 

Absolutely, i often play the which lane will be fastest game haha

 

its usually lane 1 or lane 2 again as everyone seems to move straight across into lane 3 and 4.

 

Oh its a funny world we live

[jthompson]

The lane hogging thing I find quite confusing. I can understand it (although it's still poor driving) when there is a fair amount of traffic, as some people may feel as though they'd be 'trapped' behind a lorry if they made any use of the inside lane. But when the motorway is basically empty, it's just confusingly moronic.

 

I put it down to a combination of two things:

• Inattention (i.e. not noticing what other vehicles are doing or what is happening in other lanes).
  
• A misconception about lanes, and thinking that it's like a swimming pool with lanes graded progressively from slow to fast.
  

 

With all the gadgetry making its way into cars nowadays, I do wonder if a combination of adaptive cruise control and blind spot detection could be developed a little further to make a "lane return" suggestion after passing a vehicle, or of the lane to the left is clear.

[RedwayNetworks_Michael]

The lane hogging thing I find quite confusing. I can understand it (although it's still poor driving) when there is a fair amount of traffic, as some people may feel as though they'd be 'trapped' behind a lorry if they made any use of the inside lane. But when the motorway is basically empty, it's just confusingly moronic.

 

I put it down to a combination of two things:

• Inattention (i.e. not noticing what other vehicles are doing or what is happening in other lanes).
  
• A misconception about lanes, and thinking that it's like a swimming pool with lanes graded progressively from slow to fast.
  

 

With all the gadgetry making its way into cars nowadays, I do wonder if a combination of adaptive cruise control and blind spot detection could be developed a little further to make a "lane return" suggestion after passing a vehicle, or of the lane to the left is clear.

 

This is true, although lane 2 is much less likely to be stuck behind lorries so not sure why they like lane 3 and 4 haha

 

As for your point around the new car tech, this is a million pound idea, sadly someone is now likely in process of taking this idea and making millions hahaha