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The Transporter
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Discussion Starter · #1 ·
Excluding, of course, those parts of the Autobahn system where 130 is just suggested.

Some italian "autostrade" have in plan the introduction of a 150 limit, thanks to a law permitting this at certain conditions.
Most important points are:
- 3 lanes + shoulder
- "Tutor" system (average speed control) on the whole stretch
- low accident rate in the last years.

Although I am one of the few who sticks to the limit (so a higher limit would be nice for me), I still doubt this can be a safe project.

I have many cons about this 150-thing, and I'll expose them later in this thread.

First, I'd like to know if highways with 130+ limits exist, and at which conditions.

Main example is: some parts of the Autobahnen have no posted limits, BUT 130 is posted as a suggested speed; this has a legal meaning, since if you get involved in an accident (even with no personal fault) and the Police have evidence that you were travelling in excess of 130, you may be held a part of responsibility, and your insurance might refuse to pay.
So, the point is: do it at your own, huge risk.

Other systems with no posted limit? Or with a posted limit >130?
Is there any Autobahn with a posted limit >130?
 

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In Slovakia there have been plans to introduce 160 km/h speed limit at some sections of motorways. It's legally possible, but some modifications have to be done such as jersey barriers in the median, longer acceleration and deceleration lanes and electronic signage.

This is quite expensive and we don't really have money for that right now due to the crisis. On the other hand jersey barriers and electronic signage would be quite useful even without introducing higher speed limit. Frankly, I think it's waste of money. Proposed sections are rather short so higher speed limit would bring basically no time saving.


There are two sections of motorways which were designed for speed 150 km/h, which means their curves, slopes and length of acceleration and deceleration lanes are appropriate for speed 160 km/h. It's D1 between interchange Bratislava Vajnory and Senec (16.8 km) and D2 between interchange Bratislava Lamač and Czech border (58 km).

The first section has high traffic volumes and it has been recently converted into temporary 2x3 road without hard shoulder so introduction of higher speed limit is obviously impossible. The latter one would be much more suitable for higher speed limit as traffic is much lower there, but it's the oldest motorway in Slovakia (completed in 1978) and now it's far from being in perfect shape. However, after complex reconstruction which has to be done sooner or latter this would be a perfect candidate for 160 km/h speed limit.

There are also other old sections of motorway which have to be reconstructed so we may expect higher speed limit also there. Some new sections of expressways are to be designed for higher speed, at least that's what former CEO of our National Motorway Company said, but I don't believe in it because majority of them is in quite tough terrain.
 

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The Transporter
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Discussion Starter · #3 ·
but some modifications have to be done such as jersey barriers in the median, longer acceleration and deceleration lanes and electronic signage.
Thank you, very interesting :cheers:

Some more questions:
1) Is the average driver skilled enough, to drive in such a fast traffic?

2) About fines: speed controls are effective enough to ensure that limit is not violated? And the fines would be higher?
I mean, my main concern about the 150-thing is that they're doing it not to permit a standard 150 speed, but to let racers fly over 170 with a small fine.
 

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IsraCanadian :)
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I actually think it is a great idea - introduce a "hard" speed limit that cannot be easily violated by using averaging speed cameras, but make the limit relatively high. This way you eliminate (or at least greatly reduce) the worry that whatever limit you introduce, people will always drive significantly faster (which isn't really true anyway, according to the 85-percentile rule).

I do think that 150 or 160 is a little excessive. Except for those cases when one wants to test a car's performance, such high speed limits are essentially equivalent to no restriction at all.

I wish we here in Ontario had a 130 km/h limit on our motorways instead of 100, and then I would even support strict enforcement using averaging cameras.
 

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The Transporter
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Discussion Starter · #6 ·
Very good. In this case, is still valid the "suggested speed" rule, which I described in the first post?

And, are there also examples of the 140 limit on the A2 being fixed (with a standard signal) and not variable?
 

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No its not. The "suggested" speed is signed in white on a blue square (and can in fact be found only at boarders). That is a normal speed limit up there.
 

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The Transporter
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Discussion Starter · #9 · (Edited)
That's not what I meant, but it's my fault: my question was not so well explained :)

As far as I know, when there are no posted limits, the "suggested speed" rule means that, if you drive higher than 130, in case of accidents you may face legal issues.
So my doubt is: if the legal limit is fixed at 140, and you travel at that speed, and you have an accident, do you still risk legal problems for being over 130?
 

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IMO a 150 km/h speed limit on 2x3 (on 2x2 130 km/h is enough) motorway should be posted only if Wilhem275s conditions would be met AND:
  • The driver is at least 25 years old and owns a full drivers licence for 5 years AND he didn't get any speeding ticket during the last 12 months
  • The road is not very busy every day
  • If you pass 150 km/h, speed fines must be very HIGH (higher than on a normal 130 km/h section)
  • Long accelerating and decelerating lanes
  • The road has to be as straight as possible, with curves that have a radius designed for 160 km/h
  • The road has to be recently paved, so the asphalt is in good condition
  • Electronic signage over each lane to announce drivers to reduce speed in case that something happened (accident, low visibility, busy road etc.)

    later edit: it also has to be a rural motorway and a perfect weather
 

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I wish we here in Ontario had a 130 km/h limit on our motorways instead of 100, and then I would even support strict enforcement using averaging cameras.
Most of the 400-Series Highways have a design speed of 150 km/h, but it's only posted at 100 km/h. I would like to see rural, less traveled sections get posted to 120 or 130, but I doubt it will ever happen.

One more thing, the weather conditions have to be perfect. In France I remember seeing a sign that said 130 in sunny conditions, 110 during the rain and at night.
 

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In the United States, only some highway segments in Utah have legal 130 km/h (80 mph) speed limits. Other states' legal speed limits range from 88 km/h (55 mph) to 120 kmh (75mph). However, since most limited access highways are 2x3 to 2x6, the speed of 85 percent of free-flowing traffic is about 80 mph (130 km/h), regardless of the posted speed limit, because that feels like the most natural and safe speed to drive on that kind of highway. It's not uncommon to see cars going at 145 km/h (90 mph) safely.

Most speed limits in the United States are set politically instead of scientifically and often are set far lower than road design and conditions allow so as to generate traffic fine revenue for state and local governments.

What's really dangerous are the young men in street bikes, like Suzuki Hayabusas, driving at speeds over 125 mph (200 km/h) when everyone else is going between 70 and 80 mph (110-130 km/h).

Here's a web page with lots of links about speed limits: http://www.motorists.org/speed-limits/
 

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88 km/h (55 mph) way to slow on a motorway. I would accept such a low speed limit only if it was a urban motorway.
 

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Thank you, very interesting :cheers:

Some more questions:
1) Is the average driver skilled enough, to drive in such a fast traffic?

2) About fines: speed controls are effective enough to ensure that limit is not violated? And the fines would be higher?
I mean, my main concern about the 150-thing is that they're doing it not to permit a standard 150 speed, but to let racers fly over 170 with a small fine.
1) I don't think average driver would drive that fast. Not everybody would like such fast driving, not to mention not everybody's car can reach such speed and even if it can reach it the fuel consumption is pretty high.

2) According to current legislation fines wouldn't be higher. Of course, the limit should be regularly enforced. There's no reason for anybody to drive faster than 150/160 and IMO if someone break this limit for more that let's say 10 km/h fines should be higher.

Unfortunately, there's plenty of people who drive about 150 km/h also now when the limit is 130. If I drive in faster lane it's only matter of seconds maybe few minutes until some car driving 150 will appear in my rear window.
 

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Austria has experimented with a 160 km/h limit on the A10 a while back.
And how did the experiment go? Are there any motorways in Austria with a speed limit over 130?
 

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1)Unfortunately, there's plenty of people who drive about 150 km/h also now when the limit is 130. If I drive in faster lane it's only matter of seconds maybe few minutes until some car driving 150 will appear in my rear window.
Maybe the speed limit is set too low at 130 km/h and an engineering study should be made to see if it should be raised to 150 km/h. Remember that 85 percent of the people drive at the safest speed for the conditions of the particular road regardless of what's posted. In other words, if 150 is the safest speed, people will drive at 150 irrespective of whether they post a speed limit sign saying 120 or 180. When a speed limit is scientifically set according to the 85th percentile method, only 15% of drivers will go significantly above or below the 85th percentile speed.
 

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88 km/h (55 mph) way to slow on a motorway. I would accept such a low speed limit only if it was a urban motorway.
The double-nickel (55 mph) national speed limit was set in 1974 as a way to save gasoline after the 1873 oil crisis and was widely ignored but was enforced because states who didn't enforce it lost a portion of their federal highway money.

In urban limited-access highways, the speed limit should be whatever is safe for the design and characteristics of the road and the road conditions. When there is congestion, the congestion itself regulates the speed limit by forcing drivers to slow down without the need for any sign, so there is really no need to set different speed limits based on the character of the area outside the highway.
 

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Maybe the speed limit is set too low at 130 km/h and an engineering study should be made to see if it should be raised to 150 km/h. Remember that 85 percent of the people drive at the safest speed for the conditions of the particular road regardless of what's posted. In other words, if 150 is the safest speed, people will drive at 150 irrespective of whether they post a speed limit sign saying 120 or 180. When a speed limit is scientifically set according to the 85th percentile method, only 15% of drivers will go significantly above or below the 85th percentile speed.
I would say majority of people respect the limit. Speeding minority is just more visible. 130 is quite reasonable speed. Trucks and buses drive slower of course and plenty of cars too to save the fuel. And even if some people drive faster, only few cars are driving more than 140, but those few cars frequently appear in your rear window.
 
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