Increase Speed limit on motorways?

oppenheimer1

Its a little known fact that Irish motorways are designed to carry traffic at speeds of up to 160km/h (100mph) safely. With this in mind should the speed limit on these roads be increased, beccause in fairness its not where many of the serious accidents happen. Or is the environmental effect too great? If there was a motorway that stretched from Dublin to Galway it would knock 25mins off the journey time, bringing the travelling time down to just under 1hr 40mins.

So what do we think?

(I would have put this in motors, but they are all speed freaks over there )

<edit> Hmm, it seems this has been moved... oh well

Rabies

say hello to the freaks!

Motors stuff --> motor forum
random stuff --> After hours

stuff --> stuff forum

JHMEG

I recently read somewhere that (in a small 1.2L car) every 40km travelled on motorway at 120km/h costs an additional €1 in fuel costs over travelling the same route at 90km/h.

The journey to Galway might be quicker, but how much more expensive is it?

Pete4779

it should but it should be on a lane basis. The right hand lane should be clearly up to 160kph, and the left lane 100kph for trucks and slower cars.

oppenheimer1

JHMEG wrote: »

I recently read somewhere that (in a small 1.2L car) every 40km travelled on motorway at 120km/h costs an additional €1 in fuel costs over travelling the same route at 90km/h.

The journey to Galway might be quicker, but how much more expensive is it?

I would have to do some calcs, but I shall get back to you on that. This may take a while!

sdanseo

This could have stayed in AH, would have been better there as its random enough; and the poll would have been considerably less biased - not that I'd ever question a mod :P

Pete4779 wrote: »

it should but it should be on a lane basis. The right hand lane should be clearly up to 160kph, and the left lane 100kph for trucks and slower cars.

The outside lane is for overtaking. You should be in the furthest left lane at all other times, even if there's 3 or 4 of them. Basic motoring knowledge that.

Motorway limit should be 140km/h, a two lane motorway with as many idiot drivers as we have would be asking for trouble with anything higher, unfortunately. While most of us here could easily do 180km/h safely, many would continue doing so dangerously while twats would stay doing 80km/h because the don't like fast roads. These folks should NOT be on the motorways.

congo_90

From a theory of mine:

We would fit less cars per hour on a motorway by raising the speed limits

We would get places faster but depending on your speed v's the original speed /Distance travelled.
Example of above is a journey I take regularly. At 100km/h an increase of 20km/h reduces my time by around 7minutes

I'd like to see someone link a source to where irish roads were designed for such speeds. I'm not questioning op, just this has been around motors before and noone in my time has shown how.

There is an increase in fuel consumption to be factored in. A lot of cars i've driven 1.0-1.6 range seem most efficient at 80- 90km/h.

While a lot of drivers claim to be able to handle such speeds and probably can. I don't believe irish motorists in general could be trusted at such speeds. Sad I know.

Anyways thats my 2cent

JHMEG

oppenheimer1 wrote: »

I would have to do some calcs, but I shall get back to you on that. This may take a while!

On a very basic level the M4/M6 motorway goes to Ballinasloe and is ~129km, or about 3x40km. So a return journey at 120km/h vs 90km/h will cost and additional €6 in fuel.

Run_to_da_hills

Pete4779 wrote: »

it should but it should be on a lane basis. The right hand lane should be clearly up to 160kph, and the left lane 100kph for trucks and slower cars.

And keep the hard shoulder for idiots that do under 50 KPH.

Owandy

While a lot of drivers claim to be able to handle such speeds and probably can. I don't believe irish motorists in general could be trusted at such speeds. Sad I know.

Anyways thats my 2cent[/quote]

It's a sad fact, but true, a massive number of people in this country are clueless when it comes to motoring. I've had some hairy moments on Motorways with people changing lanes without indicating to overtake someone when their speed barely matches the car they're trying to overtake forcing me to brake too hard for the speed I'm doing. Increase that risk by another 20-40kmph? No thanks. I'd love to get to Galway quicker, but I'd be much happier knowing I will, in fact, get there!

Rabies

sdonn wrote: »

This could have stayed in AH, would have been better there as its random enough; and the poll would have been considerably less biased - not that I'd ever question a mod :P

A redirect is left in AH for regular forum users to follow.

Motor topics get discussed in Motors.

Posting polls in AH is worst thing to do at times, the mentality of some of the users leaves a lot to be desired at times. Polls can get twisted.

Nothing is stopping regular AH people going to Motors and giving their views.
Boards doesn't revolve around AH.

Capt'n Midnight

we should hold off any discussion until Irish drivers learn how to use motorways as safely as the rest of the EU are able to do

things that need to happen first
- there is proper respect for and enforcement of keeping left
- speed limits are enforced - just look at how few trailers travel at 80kph
- sane merging
- lane dicipline
- separation from vehicle in front

probably we should wait until NI drivers can get penalties down here too

At present there are too many people driving in the middle lane
too many cutting across lanes to dive into the exit

congo_90

Just to ad to my point earlier. If we completly renewed the awareness of motoring using a reviewed driving test/ training then maybe just maybe we could safely go at such speeds. As it is there is no formal training or test on motorways.
The best I got was 400M of N3 with my tester and only up to 100km/h for the best part of 200M.

squod

Pete4779 wrote: »

it should but it should be on a lane basis. The right hand lane should be clearly up to 160kph, and the left lane 100kph for trucks and slower cars.

There's a million people out there, people who don't know what an overtaking lane is.

The speed limit should be inceased for drivers who have passed an additional 'advanced motoring test' IMO.These people could then be licensed to drive more quickly on motorways.

There'd still be the people though, blocking the overtaking lanes up. What can we do with them?

oppenheimer1

congo_90 wrote: »

From a theory of mine:

We would fit less cars per hour on a motorway by raising the speed limits

We would get places faster but depending on your speed v's the original speed /Distance travelled.
Example of above is a journey I take regularly. At 100km/h an increase of 20km/h reduces my time by around 7minutes

I'd like to see someone link a source to where irish roads were designed for such speeds. I'm not questioning op, just this has been around motors before and noone in my time has shown how.

There is an increase in fuel consumption to be factored in. A lot of cars i've driven 1.0-1.6 range seem most efficient at 80- 90km/h.

While a lot of drivers claim to be able to handle such speeds and probably can. I don't believe irish motorists in general could be trusted at such speeds. Sad I know.

Anyways thats my 2cent

Sorry this has taken a bit but here are the numbers in terms of increased fuel consumption.

Source AutoBild Magazine 2006
http://bioage.typepad.com/.shared/image.html?/photos/uncategorized/autobild1.png
Model VW Golf 1.4TSI
Distance: 213km (132 miles)

Miles per gallon (US) @120km/h (75mph): 29
Miles per gallon (US) @160km/h (100mph):20

So thats 4.55USGal @120km/h and
6.60USGal @160km/h

So an increase in consumption of 7.7l
@117c/l
gives an increased cost of €9.07 per one way journey or 45% over original cost.

So if you value your time at more than €20/hr it may be worth it.
I have noticed that this doesn't make much of a case for increasing the speed limit, however the speed limit isn't a target, one should at least have the option of using the road at the speed it was designed for. Sorry I can't give a link to confirm the design speed, but I know its in their design guide.

JHMEG

oppenheimer1 wrote: »

gives an increased cost of €9.07 per one way journey or 45% over original cost.

You are saying €9 to save 25 mins? Or €18 return? Is it really that bad?

How does 160km/h vs 90km/h compare?

Rabies

i think we'd need three lane motor ways to cope with it. not the two lane and typical irish drivers

oppenheimer1

JHMEG wrote: »

You are saying €9 to save 25 mins? Or €18 return? Is it really that bad?

How does 160km/h vs 90km/h compare?

€9 to save 25 mins

Yes its expensive. Air resistance increases by square proportion I think (ie double the speed, 4 times more resistance)

For 160km/h vs 90km/h

Same model and distance as before.

Consumption
Miles per US Gal @ 90km/h: 39

Therefore giving a consumption of 3.38 US Gal for trip or 12.79l
Trip costs €14.96 @117c/l @90km/h
Trip costs €29.21 @117c/l @160km/h

Time taken 2.36hrs @90km/h vs 1.33hrs @160km/h

Time saved 1.03hrs for a cost of €14.25.

Rabies

You guys are reading too much in to this.

The question is:

Do you want to drive faster on irish motorways

Yes or No.

Leave the science and the few euros behind.

Voodoomelon

As much as i'd LOVE to see the motorway limit increased, I reckon it would only cause more accidents in this country.

It's bad enough seeing people making mistakes at 100-120kph, I can't fathom what things would be like at 160kph. That kind of speed is far less forgiving.

Couple that with the amount of drivers who hog the overtaking lane at 120kph, can you only imagine what things would be like with an increase to 160kph? You'd have far more risk takers, aggression and general mayhem.

At least teach drivers how to use a motorway first, then consider increasing the limit.

Yakult

Rabies wrote: »

You guys are reading too much in to this.

The question is:

Do you want to drive faster on irish motorways

Yes or No.

Leave the science and the few euros behind.

yes :pac:

Stephen

I'd like to see some mpg vs speed figures for cars with proper engines, not the poverty spec weedy engines most people buy here.

Lord Nikon

It depends on the car. Remember the Top Gear test between the M3 and the Prius

https://www.youtube.com/watch?v=dKTOyiKLARk

I think my 520 would be more economic at 100mph than a Nissan Micra at 100mph...

Oh, I forgot the question, eh, increase the motorway speeds.

Anan1

Pete4779 wrote: »

it should but it should be on a lane basis. The right hand lane should be clearly up to 160kph, and the left lane 100kph for trucks and slower cars.

So a car travelling at the current 120km/h limit would be forced to block the overtaking lane of a 160km/h rated motorway?

Zube

Once outside Dublin, 140 is quite normal on the motorways already.

dudara

Three points:

1. Most modern cars are capable of those speeds
2. Most motorways are capable of those speeds
3. Most Irish drivers are not capable.

I drive the N7/M7 regularly. It's a scary experience most days and turns into an absolute disaster zone when it starts to rain.

We simply cannot contemplate such an scenario until we have a well-educated driving population. We're getting there, but we have quite a way to go too.

Zube

dudara wrote: »

We simply cannot contemplate such an scenario until we have a well-educated driving population.

What scenario? Making everyday motorway speeds legal?

The logical alternative is to police the motorways and give everyone tickets until they slow down, but we all know that won't happen.

So, we'll continue to have a stupidly low but completely unenforced limit which everyone ignores. This will be useful when there is a major pile-up, since Gaybo will be able to blame it on speeding instead of having to think.

dudara

Zube wrote: »

So, we'll continue to have a stupidly low but completely unenforced limit which everyone ignores..

Are you referring to the 120 kmph speed limit? That can hardly be called stupidly low. And it's clear from driving on the motorway that a fair heft of Irish drivers aren't comfortable at that speed.

The Real B-man

I dont think Irish Drivers would be able to cope with those Speeds it would just be Pure Carnage and there isnt long enough stretches and they seem to be doing the Oposite like the 100Kph Limit on the M50 Between the Airport & Sandyford. :rolleyes:

Cookie_Monster

The Real B-man wrote: »

I dont think Irish Drivers would be able to cope with those Speeds it would just be Pure Carnage...

...for a few months until the idiots are weeded out:D

norrie rugger

dudara wrote: »

Are you referring to the 120 kmph speed limit? That can hardly be called stupidly low. And it's clear from driving on the motorway that a fair heft of Irish drivers aren't comfortable at that speed.

Then the cops should be patrolling the motorways more and people who are not suited to Motorways should not be on them

Edit: having cops on their little embankmants, with radar guns, is not patroling.
They should be in unmarked, looking for dangerous/careless driving.

Everyone who does the n7/m7 on a Friday afternoon would tell you, that they would not be driving long to catch someone

GigaByte

JHMEG wrote: »

I recently read somewhere that (in a small 1.2L car) every 40km travelled on motorway at 120km/h costs an additional €1 in fuel costs over travelling the same route at 90km/h.

The journey to Galway might be quicker, but how much more expensive is it?

Depends on how much you value your own time?

dudara

norrie rugger wrote: »

Everyone who does the n7/m7 on a Friday afternoon would tell you, that they would not be driving long to catch someone

There's a red Mondeo cop car somewhere around J6 who regularly has people pulled over the in the morning. He had someone in a Saab this morning around 8.20am.

Liamario

A speed limit increase on the motorways would be absolutely madness. A high percentage of cars are already driving well above the speed limit as it is. If you decide to increase it, they'll go well above the new speed limit as well. You kids are never satisified

Cookie_Monster

Liamario wrote: »

A speed limit increase on the motorways would be absolutely madness. A high percentage of cars are already driving well above the speed limit as it is. If you decide to increase it, they'll go well above the new speed limit as well. You kids are never satisified

I don't think so. People find a speed thats comfortable for them and cruise at it. IMO this is usually around 130-140. For me any higher and the car starts to get a little light and gets too loud on the road.

140 I think would be a sensible speed for a lot of our motorways and would be more readily adhered to than 120 IMO

gyppo

Until Irish driving standards improve dramatically, it would be lunacy increasing speed limits on motorways.

jimbling

The danger with increasing the speed limits on any road in this country is that the general driving population are complete idiots and can't tell the difference between a max limit and a safe limit for their car and the surrounding conditions.

There are too many small engined cars that become death traps at 120 km/h, never mind 160 km/h. And a lot of the drivers of said cars would just say "well, it's legal to drive that speed, so it must be okay".

This is the main reason for silly speed limits all over the country.

Capt'n Midnight

http://en.wikipedia.org/wiki/Road_traffic_safety

For occupants, Joksch (1993) found the probability of death for drivers in multi-vehicle accidents increased as the fourth power of impact speed

so 160Kmph accidents are 6.4 times as deadly as 100kmph accidents

many road traffic casualties are not drivers (in the UK only 40% of casualties are drivers), and those measures which increase driver safey may, perversely, increase the risk to these others, through risk compensation.

risk compensation - means that in practice "safety improvements" just allow drivers to take more risks. This means that other road users are now less safe. Allowing people who think they can drive safely because of ABS and air bags to drive at 160Kmph on motorways that several times more dangerous than the best in Europe is tantamount to murder.

I like the French system of lower speed limits in bad weather
I like the UK system of variable speed limits on the ganteries.

We have the newest motorways in EU so we can't blame road quality for carnage.

smash

Forget about increased fuel consumption, because a limit is say 160... you don't have to drive at 160! If people are worried about burning fuel then stay at a lower speed... in the left lane please!

Liamario

Hold on there. You can't have cars going 140-160 km/h in the outside lane with all the other cars going 20-40 km/h slower. It's a horrific accident waiting to happen

smash

Liamario wrote: »

Hold on there. You can't have cars going 140-160 km/h in the outside lane with all the other cars going 20-40 km/h slower. It's a horrific accident waiting to happen

It happens at the moment... I often come across people travelling 80kmh on the M50/M11 in a 120 zone!

Saab Ed

steve06 wrote: »

It happens at the moment... I often come across people travelling 80kmh on the M50/M11 in a 120 zone!

and usually in the most outside lane brake testing you....

You could give Irish ten lanes they'll still always be as far to the right as they can be

Liamario

So you want to have these shenanigans going on at a much higher speed as well as making it legal?! :eek:

jimbling

Capt'n Midnight wrote: »

http://en.wikipedia.org/wiki/Road_traffic_safetyso 160Kmph accidents are 6.4 times as deadly as 100kmph accidents risk compensation - means that in practice "safety improvements" just allow drivers to take more risks. This means that other road users are now less safe. Allowing people who think they can drive safely because of ABS and air bags to drive at 160Kmph on motorways that several times more dangerous than the best in Europe is tantamount to murder.

I like the French system of lower speed limits in bad weather
I like the UK system of variable speed limits on the ganteries.

We have the newest motorways in EU so we can't blame road quality for carnage.

Ya that's all pretty straight forward.... and I definitely agree with lower speed limits in bad weather.

But by the way, "safety improvements" aren't all about what happens to the driver when they crash. ABS breaks and Traction control are there to prevent a crash also. But in a sense you are right. Obviously the faster the car is going the more carnage it will cause overall if it crashes.

But this carnage you talk of... how much of that happens on motorways? This continuously comes up, and I never really see an answer.
I always presume that most road deaths happen on secondary roads... no idea if that is correct though. Is there actual stats for it?

Liamario

For me personally as fairly inexperienced driver, the worst driving I see is on the motorway, which is made even more potent by the fact that I am rarely on the motorway

Zube

Capt'n Midnight wrote: »

so 160Kmph accidents are 6.4 times as deadly as 100kmph accidents

So we should lower the motorway limit to 50 kph, that would be much safer, right?

We did not build motorways so that we could tootle about safely and economically at 50 kph. We need them so that the 200 km from Galway to Dublin will take one and a half hours instead of four, and 250 km Cork to Dublin will be under 2 hours instead of seven.

JHMEG

JHMEG wrote: »

I recently read somewhere that (in a small 1.2L car) every 40km travelled on motorway at 120km/h costs an additional €1 in fuel costs over travelling the same route at 90km/h.

The journey to Galway might be quicker, but how much more expensive is it?

I would rather pay more and get to my destination faster.

JHMEG

GigaByte wrote: »

Depends on how much you value your own time?

Depends. A lot of the time it's people rushing to get home to do something non-productive like watch TV.

craichoe

I drive on unrestricted autobahn every week,

I normally cruise at 130 - 140, although have on occasion done 220 - 230.

You eventually have to slow down due to trucks overtaking, but on a 100km journey theres only 5 minute difference between booting it and tootling along and keeping an average speed of 130 - 140.

You'll eventually catch up with the lad driving that Porsche 996 that went past you so fast, your car wobbled from the Vortex in his wake

in a traffic jam 30 km up the road

godtabh

oppenheimer1 wrote: »

Its a little known fact that Irish motorways are designed to carry traffic at speeds of up to 160km/h (100mph) safely.

Can you back that up?

bazzachazza

Absolute madness I think.

We have 3 lane Motorways and Dual carriageways and the feckin idiot Irish drivers now sit in the 2 lanes to the right so it certainly isn't the answer.

Most Irish drivers are NOT capable of driving at higher speeds.

And simply stating "I am a good driver" does not make you a good driver.

Its a little known fact that Irish motorways are designed to carry traffic at speeds of up to 160km/h (100mph) safely.

The section of the M50 MOTORWAY south of Tallaght to Sandyford WAS NOT MADE FOR 160km/h speeds.