Speed limiters on new build cars

[Tetchytyke]

My car "reads" road signs but, as it was originally registered in England, it interprets the black diagonal line on white as "60mph".

Helpful as here it doesn't mean "national speed limit", it means "end of speed limit".

It's fine when it's just a picture on my dashboard, not so good if my car chose to limit itself to 60.

smart motorways were, imo, a kneejerk reaction to not enough motorway capacity, we all know the consequences of that decision

Smart motorways have existed in Germany for a long time and there are no issues.

The problem in the UK is that, as always, they try and do it on the cheap.

 

[Iskra]

My car "reads" road signs but, as it was originally registered in England, it interprets the black diagonal line on white as "60mph".

Helpful as here it doesn't mean "national speed limit", it means "end of speed limit".

It's fine when it's just a picture on my dashboard, not so good if my car chose to limit itself to 60.



Smart motorways have existed in Germany for a long time and there are no issues.

The problem in the UK is that, as always, they try and do it on the cheap.

The national speed limit can be 70 here, so 60 would be incorrect anyway.

 

[Hans]

My car "reads" road signs but, as it was originally registered in England, it interprets the black diagonal line on white as "60mph".

Helpful as here it doesn't mean "national speed limit", it means "end of speed limit".

It's fine when it's just a picture on my dashboard, not so good if my car chose to limit itself to 60.



Smart motorways have existed in Germany for a long time and there are no issues.

The problem in the UK is that, as always, they try and do it on the cheap.

Yes you are right about doing it on the cheap, to me that goes back to proper research and analysis. There is a distinct lack of critical thinking with many, easy, cheap solutions appear to be the order of the day for many.

 

[cactustwirly]

Reading through the events being discussed in this thread I’m starting to come to the conclusion myself that it’s time to introduce something to restrict vehicles from being able to be driven like that.

It’s obviously going to happen eventually isn’t it?

It just needs more enforcement and speed cameras in urban areas

 

[Tetchytyke]

The national speed limit can be 70 here, so 60 would be incorrect anyway.

I think it displays 70 on dual carriageways, using GPS/SatNav data, but truthfully I can't remember as there are no dual carriageways here.

 

[gg1]

My car "reads" road signs but, as it was originally registered in England, it interprets the black diagonal line on white as "60mph".

Helpful as here it doesn't mean "national speed limit", it means "end of speed limit".

It's fine when it's just a picture on my dashboard, not so good if my car chose to limit itself to 60.

Mine does too, the problem is it doesn't do so reliably.

When there is a change in the speed limit identified by standard signs it sometimes misses the change while on variable speed limit motorways it actually misses speed limit changes on the gantry signs more often than it detects them. Then there's the problem of it detecting speed limit signs on side roads or slip roads instead of the road I'm actually travelling on. Not a major problem at the moment when all it does is display it on the dashboard but if a car with the active speedlimiters had the same problem it could be incredibly dangerous, eg forcing my speed down to 30mph on a 70mph dual carriageway.

I'm not convinced GPS would solve the problem either, every system I've used occasionally fails to correctly detect my current location, and even when working perfectly it's no use for variable or temporary speed limits.

 

[Hans]

It just needs more enforcement and speed cameras in urban areas

The people who drive like idiots though will always do it irrespective of speed cameras. Enforcement and revenue generating cameras are not the answer, educating drivers would be a better option especially younger drivers about the issue of speed, there should also be education about driving too slow, or the 40mph drivers who think they are safe driving everywhere at that speed, so ignoring minimum motorway speeds and 30mph or lower limits.

 

[mmh]

My car "reads" road signs but, as it was originally registered in England, it interprets the black diagonal line on white as "60mph".

Well that system was rubbish and should never have been used in the UK as the national speed limit is different depending on the road you're driving on and the vehicle you're driving.

 

[LOL The Irony]

People must take responsibility for their own actions, they must make their own risk assessments, there is a place for laws and restrictions, but there is also over interference in peoples lives which many government bodies are very reluctant to take away once it is implemented.

This is the problem. People would rather we become a complete nanny state than allow people to be personally responsible for their actions. I wonder if these same people were told that the more we become a nanny state, the more our freedoms become compromised and restricted, if they'd still agree to the state deciding things for us?

Japanese imports would suddenly become very popular if limiters were introduced…

With the 112 (113?) mph limit imposed on JDM cars, that would depend on what our limiters would be set at.

I think it displays 70 on dual carriageways, using GPS/SatNav data, but truthfully I can't remember as there are no dual carriageways here.

Not all dual carriageways are 70 though. If it's unbarriered, it's 60. But even then, we've had 70mph single carriage roads.

It just needs more enforcement

Yes.

speed cameras in urban areas

No. Speed cameras make you concentrate on your speedo, not the road ahead. I'd personally rather people do 35 than not see the person step out into the road. A HUD displaying speed could fix this, but it's usually an additional cost.

The people who drive like idiots though will always do it irrespective of speed cameras. Enforcement and revenue generating cameras are not the answer, educating drivers would be a better option especially younger drivers about the issue of speed, there should also be education about driving too slow, or the 40mph drivers who think they are safe driving everywhere at that speed, so ignoring minimum motorway speeds and 30mph or lower limits.

If I were PM, I'd put you in charge of my road strategy.

 

[Domh245]

Eventually yes, but thus far GPS isn't quite good enough yet.

Give it 10 years.

For a full "this road is 40, this road is 60" dynamic limiter, yes. For a "you're not doing more than 90mph unless you're at Brands Hatch, Silverstone, Beford Aerodrome*, etc, or outside of the UK" blanket limiter I think that should be quite easily implementable tomorrow. Even if you don't precisely geofence it to the track limits themselves, putting a central coordinate and acceptable radius would be more than fine - yes you could theoretically do some high speeds on roads near the area but you then traffic calm/heavily enforce limits on those conventionally if they actually pose a risk

This is the problem. People would rather we become a complete nanny state than allow people to be personally responsible for their actions. I wonder if these same people were told that the more we become a nanny state, the more our freedoms become compromised and restricted, if they'd still agree to the state deciding things for us?

I dislike overregulation as much as the next man, but it takes a special type of heartlessness to say "it's fine for someone to drive at 140mph because they'll be personally responsible (whatever that actually means) if they cause death or serious injuries" when for very little cost you can stop them from ever going above 90mph outside of suitably safe and controlled locations. Not least as them "being personally responsible" means f.a. and has resulted in unnecessary costs incurred on the NHS, and likely accommodating the driver at Her Majesty's pleasure (and her taxpayer's expense)

There are some areas where it's either plainly obvious, or otherwise agreed on by consensus, that regulation is necessary. Improving safety by preventing vehicles from doing double the legal speed limit seems like one of those situations.

Not all dual carriageways are 70 though. If it's unbarriered, it's 60

I can't say I've ever heard of this case, source please?

 

[Ediswan]

Not all dual carriageways are 70 though. If it's unbarriered, it's 60.

Source please.

 

[Hans]

This is the problem. People would rather we become a complete nanny state than allow people to be personally responsible for their actions. I wonder if these same people were told that the more we become a nanny state, the more our freedoms become compromised and restricted, if they'd still agree to the state deciding things for us?

With the 112 (113?) mph limit imposed on JDM cars, that would depend on what our limiters would be set at.

Not all dual carriageways are 70 though. If it's unbarriered, it's 60. But even then, we've had 70mph single carriage roads.

Yes.

No. Speed cameras make you concentrate on your speedo, not the road ahead. I'd personally rather people do 35 than not see the person step out into the road. A HUD displaying speed could fix this, but it's usually an additional cost.

If I were PM, I'd put you in charge of my road strategy.

I have HUD and I am really pleased with it and think it should be standard on all cars.

When you get the PM's job, give me a call!

 

[mmh]

Not all dual carriageways are 70 though. If it's unbarriered, it's 60. But even then, we've had 70mph single carriage roads

Not true, whether a road is barriered or not doesn't affect its speed limit if it is a national speed limit road.

Perhaps we do actually need technology (sigh) when people don't actually know what the national speed limits are.

 

[Bald Rick]

But even then, we've had 70mph single carriage roads.

Have we? Where?

 

[skyhigh]

A mandatory upper limit of 70mph would soon become 50mph and so on. With technology will it then become due to "climate change" all cars will now be limited to 20mph and the technology is there to ensure they do.

Would it...? I'd take the tinfoil hat off.

 

[Tetchytyke]

the 40mph drivers who think they are safe driving everywhere at that speed

The ones who drive everywhere at 37mph are the most actively dangerous drivers out there, as they have no understanding of their surroundings and clearly can't respond to changing road conditions.

Speed cameras make you concentrate on your speedo, not the road ahead. I'd personally rather people do 35 than not see the person step out into the road

I'm not sure that's the case, at least for a reasonably competent driver. I know what speed I am doing, within 1-2mph, from the gear and engine note in both my cars. Admittedly that's harder to know in a Tesla, but still.

it takes a special type of heartlessness to say "it's fine for someone to drive at 140mph because they'll be personally responsible (whatever that actually means) if they cause death or serious injuries" when for very little cost you can stop them from ever going above 90mph outside of suitably safe and controlled locations

The ones who are going to drive a Range Rover down an urban road at 120mph and crash onto a railway line, to choose a random example, are also the ones who would immediately jailbreak/re-map any car with an electronic limiter.

 

[JamesT]

I definitely wouldn't want camera systems directly controlling allowed speed. A route I drive on regularly has the following sign:

My car normally misreads this as being a National Speed Limit sign when it's a 30mph zone.

The more dangerous one is when it picks up the 5mph signs on building sites at the side of the road. I can just ignore the red symbol on my dash, but if it tried to put the brakes on to get down to that speed...

 

[Islineclear3_1]

I rarely read signs on my dashboard, I prefer to read what's on the road

 

[swt_passenger]

Have we? Where?

Before 1977. That was when the blanket 60 mph on single carriageways started. 1973-77 had been the various oil crisis reductions, but before ‘73 main roads with a single carriageway usually allowed 70 mph.

But there’s a good concise summary of speed limit changes in the 60s and 70s in Hansard, here:

https://publications.parliament.uk/pa/cm200102/cmselect/cmtlgr/557/557ap99.htm

Disclosure, the 1973 oil crisis speed limit changes happened while I was learning to drive. I kept having to relearn the rules…

 

[66701GBRF]

Not all dual carriageways are 70 though. If it's unbarriered, it's 60. But even then, we've had 70mph single carriage roads.

To be a dual carriage way and thus 70mph (unless otherwise signed) there must be a central reservation between the two carriage ways. The central reservation does not have to be barriered. If there is no central reservation then its a single carriage way (even if there are multiple lanes) and thus 60mph is the max speed (unless signed otherwise).

At least that is how I understand it.

 

[ABB125]

Have we? Where?

I think there are a few which lead only to a motorway which are technically motorways themselves (even if the relevant highways authority doesn't understand how things like this work (though to be fair, neither do I!) and hasn't classified it as a motorway). For example, the Carrington spur (M60 J7), though I've never been along it and don't know much about it. There are a number of other examples, but I have far more important things to do than find out if they ever had a 70mph speed limit (or still do...)!

 

[AM9]

The people who drive like idiots though will always do it irrespective of speed cameras. Enforcement and revenue generating cameras are not the answer, educating drivers would be a better option especially younger drivers about the issue of speed, there should also be education about driving too slow, or the 40mph drivers who think they are safe driving everywhere at that speed, so ignoring minimum motorway speeds and 30mph or lower limits.

There's nothing wrong with enforcement cameras provided the maximum legal speed is clearly indicated (or in the case of a 30mph limt, unambiguous). If drivers wish to contribute to the revenue that the cameras enable, that's their choice. Nobody is forced to speed. (Cue some naff contrived edge case as a vain defence of law breaking).

 

[gg1]

To be a dual carriage way and thus 70mph (unless otherwise signed) there must be a central reservation between the two carriage ways. The central reservation does not have to be barriered. If there is no central reservation then its a single carriage way (even if there are multiple lanes) and thus 60mph is the max speed (unless signed otherwise).

At least that is how I understand it.

That's exactly my understanding of the rules.

There's a common misunderstanding around the definition of dual carriageways with some people mistakenly thinking it refers to the number of lanes in each direction, maybe that's the case here.

There are plenty of single carriageway roads with 2 lanes in each direction along with a (far smaller) number of dual carriageways with a single lane in each direction. If they were NSL roads the limits they would be 60 and 70 respectively.

 

[ABB125]

That's exactly my understanding of the rules.

There's a common misunderstanding around the definition of dual carriageways with some people mistakenly thinking it refers to the number of lanes in each direction, maybe that's the case here.

There are plenty of single carriageway roads with 2 lanes in each direction along with a (far smaller) number of dual carriageways with a single lane in each direction. If they were NSL roads the limits they would be 60 and 70 respectively.

See also: "dual carriageway" = 2 lanes, "motorway" = 3 lanes plus hard shoulder

 

[Bletchleyite]

To be a dual carriage way and thus 70mph (unless otherwise signed) there must be a central reservation between the two carriage ways. The central reservation does not have to be barriered. If there is no central reservation then its a single carriage way (even if there are multiple lanes) and thus 60mph is the max speed (unless signed otherwise).

At least that is how I understand it.

Correct. The presence of an Armco or similar is not relevant.

 

[swt_passenger]

I think there are a few which lead only to a motorway which are technically motorways themselves (even if the relevant highways authority doesn't understand how things like this work (though to be fair, neither do I!) and hasn't classified it as a motorway). For example, the Carrington spur (M60 J7), though I've never been along it and don't know much about it. There are a number of other examples, but I have far more important things to do than find out if they ever had a 70mph speed limit (or still do...)!

In the past it was a 70 mph motorway, but the Carrington Spur is no longer since about 2005/6, and is now the 50 mph A6144, which suggests it was eventually considered unsafe in its single carriageway motorway form.

 

[Ediswan]

There are plenty of single carriageway roads with 2 lanes in each direction along with a (far smaller) number of dual carriageways with a single lane in each direction. If they were NSL roads the limits they would be 60 and 70 respectively.

Extreme examples of both can be found here: What makes a dual carriageway

The multi-lane single carriageway is the Aston Expressway. The single lane dual carriageway is a parallel pair of country lanes near Llywel in the Brecon Beacons.

 

[AM9]

The single lane dual carriageway is a parallel pair of country lanes near Llywel in the Brecon Beacons.

On that basis then the A24 between then A246 roundabout and Burford Bridge roundabout is a 1 1/2 lane dual carriageway.

 

[gg1]

Extreme examples of both can be found here: What makes a dual carriageway

The multi-lane single carriageway is the Aston Expressway. The single lane dual carriageway is a parallel pair of country lanes near Llywel in the Brecon Beacons.

Never seen that that particular lane dual carriageway before, though have driven right past it in that section of the A40 numerous times must remember to take a small diversion to drive along it next time I'm heading that way.

Most single lane dual carriageways I've seen are stretches which were originally built as 2 lanes but later reduced to a single lane each way.

 

[ABB125]

Most single lane dual carriageways I've seen are stretches which were originally built as 2 lanes but later reduced to a single lane each way.

The A449 north of Worcester is a good example of this. South of Ombersley, the single lane section northbound is due to the alignment (I think the northbound carriageway is original, southbound was added when dualling took place). North of Ombersley, it alternates between one and two lanes in both directions due to the huge number of substandard flat crossings.