Why do people take forever to accelerate to the speed limit after a red light?

[factotum]

The only problem with the zipper method is that it relies on drivers in *both* lanes being nice and co-operating with each other--which they never do, let's be honest. You'll always get the recalcitrant *bleep* who won't let you out into his lane whether you come out early or leave it right to the cones...

[Douglas]

The only problem with the zipper method is that it relies on drivers in *both* lanes being nice and co-operating with each other--which they never do, let's be honest. You'll always get the recalcitrant *bleep* who won't let you out into his lane whether you come out early or leave it right to the cones...

Yeah, it really needs a serious effort to make following it universal, and a grass-roots approach won't work well for that - it runs into a chicken and egg problem, since anyone who tries to zipper before everyone does is just making a problem for themselves without accomplishing anything.

Getting zipper merge reliably into practice would likely require a massive coordinated public education effort, combined with widespread frequent enforcement of consequences beyond any inherent delay in traffic.

[Grey_Wolf_c]

Getting zipper merge reliably into practice would likely require a massive coordinated public education effort, combined with widespread frequent enforcement of consequences beyond any inherent delay in traffic.

Which is how we circle back to "make the driving exam challenging", and why that can't happen in a country with very poor public transportation options.

Germany has the zipper method, and I'd guess every learning driver is educated and possibly tested on it in the driver's exam. In contrast, the US doesn't even have a obligatory drivers ed process (I mean, it exists, but as I understand it most people are taught to drive by parents or friends, right?), and as vouchsafed by actual Americans earlier in the thread, the exam is a bit of a joke, so any bad habits taught by said family or friends are not going to be caught before the person gets their license.

Grey Wolf

[Douglas]

What I remember best from my drivers license exam (in America) is a specific unfairness by the examiner:

• Right at the start, getting out of the parking lot, I asked which direction to turn.
• He said he'd tell me when I had obeyed the law regarding the stop sign.
• Through the entire test, I'd get to an intersection and then get told which way to turn.
• He reported at the end that my turn signalling was weak because I didn't signal far enough in advance of a turn.

I still passed, but I was a bit pissed off about that. How the **** am I supposed to signal in advance of a turn if you won't tell me which way the turn is going to be until I'm already there?

[Iruka]

Getting zipper merge reliably into practice would likely require a massive coordinated public education effort, combined with widespread frequent enforcement of consequences beyond any inherent delay in traffic.

I am putting my hopes into the increased automation of cars. They could reliably communicate with each other to match speeds and orchestrate a smooth merge. Might still take a while to get there, however.

Germany has the zipper method, and I'd guess every learning driver is educated and possibly tested on it in the driver's exam.

It is usually taught during the mandatory lessons. You do however only get tested for it if the question happens to get drawn from the pool during the written exam or if your practical exam leads you into a situation where it is necessary.

I have to confess that I did it wrong for a long time when I was a beginner. Mostly because 90% of Germans merge early, too.

[BWR]

(I mean, it exists, but as I understand it most people are taught to drive by parents or friends, right?),olf

Most people in Norway are taught by parents. There are a few obligatory courses you have to take (a theory test, accident handling and first aid, dark driving, slippery road driving, long distance driving, and a set number of hours with a proper instructor which includes parking and city driving) but considering it will cost you upwards of 30 000 NOK (about 3750 USD) for the basic package, taking more lessons with an instructor than strictly necessary is generally avoided.

We're also supposed to use the zipper method, though I'm sure some people get annoyed at seeing people 'rush ahead' in a mostly empty lane.

[DataNinja]

It is usually taught during the mandatory lessons. You do however only get tested for it if the question happens to get drawn from the pool during the written exam od if your pracatical exam leads you into a situation where it is necessary.

I have to confess that I did it wrong for a long time when I was a beginner. Mostly because 90% of Germans merge early, too.

I'll be honest, in that I'd never even heard of the zipper method, until reading one of the editorials in the Driving section of our newspaper. It's not something taught here in Canada (or, at least not in British Columbia - Canadian education is not exactly unified in either teaching or traffic laws - my 'favorite' bit of dysfunction is how, in some provinces, a flashing green light indicates a pedestrian controlled intersection... while in others, it indicates an advanced left turn for the other side. )

[Heliomance]

What do you mean "actual" limit? A posted limit is the actual limit no matter how high it is. If the sign says 45mph the limit is 45mph.

[AMFV]

The reason I take for ever getting up to speed limit is because my car is all electric Nissan Leaf 2015 model and getting to speed limit slowly actually extends my range per charge.

Same is also true for gas vehicles.

[Rogan]

Since somebody asked about the speed limits in Germany:

In town, in general the limit is 50km/h, but often this will be redused to 30km/h in housing areas.
There are some streets wher its even lower than that. The official term is "Schrittgeschwindigkeit" meaning the speed of a human on foot, but it will usualy be interpretet as 10km/h. My driving instructor suggested first gear, no gas, but this depends strongly on the type of car.

Outside of towns, the general limit is 100km/h. It will often be lowerd to 70 near crossings or when closing on a town.

On the Autobahn, there is no upper limmit unless a sign says otherwise. But it's suggested to keep it at 130km/h (and if you are going faster, your insurance agency might reduce paymant in case of an accident)

Sometimes, there will be conditional signs, reducing the speed limit for bad weather or at night.
Sometimes, there will be warning signs, that won't reduse the speed limit to a fixed value, but if you go at the nominal speed limit and there is an accident, you get partial blame.


No matter what the spesific rules say, there is always §1, with rougly translates to:
Every participant in the public transport has to behave in such a way that it does not harm anybody else or harras them more than is unavoidable by the circumstances.

So you are allowed to go lower than the speed limit IF you have a reason for doing so.
If there is no comprehensible reason for driving slower than the speed limit, it's illegal and you can be blamed for it.

all informations from above are without engagement

[Peelee]

Yeah, it really needs a serious effort to make following it universal, and a grass-roots approach won't work well for that - it runs into a chicken and egg problem, since anyone who tries to zipper before everyone does is just making a problem for themselves without accomplishing anything.

Getting zipper merge reliably into practice would likely require a massive coordinated public education effort, combined with widespread frequent enforcement of consequences beyond any inherent delay in traffic.

The dissemination of information is the easy part. That can be slapped in the test prep manuals, on the written test, on roadside signs, etc. Enforcement would be difficult at best. And it would likely be recognized about the same as the (AL) law that headlights must be on when raining. Which is to say, total crapshoot.

If it becomes truly universal, huzzahs all around. Til then, I'ma still do it, because why should I be penalized by other people not being efficient?

[2D8HP]

...I'ma still do it, because why should I be penalized by other people not being efficient?

I've lost track, is that fuel efficient, or time efficient?

[DataNinja]

I've lost track, is that fuel efficient, or time efficient?

Space efficient, I believe.

[Douglas]

If it becomes truly universal, huzzahs all around. Til then, I'ma still do it, because why should I be penalized by other people not being efficient?

My contention there was that you trying to zipper without everyone else doing it can be creating a penalty for yourself, not avoiding one. You go all the way up to the merge point, and all the non-zipper people refuse to leave room for you, leaving you stuck waiting until you get lucky with an unusually courteous driver arriving in the other lane. The fact that you "tried to cut the line" may even make people who normally would have let you in decide not to, as punishment for your perceived offense.

This factor is, obviously, weighed against the time saved by using a nearly traffic-free lane for a bit, and where the balance on that lies depends heavily on the local driving culture. In some places, you'll be let in pretty promptly. In others, you may be forced to wait several minutes or more.

[factotum]

On the Autobahn, there is no upper limmit unless a sign says otherwise. But it's suggested to keep it at 130km/h (and if you are going faster, your insurance agency might reduce paymant in case of an accident)

I may be wrong, but aren't most cars manufactured in Germany limited to a maximum 250km/h regardless?

[Rogan]

I may be wrong, but aren't most cars manufactured in Germany limited to a maximum 250km/h regardless?

I don't know, but it is possible. But come on... do you realy want to drive faster than that?

And I just remembered:
You also have to take into account the tires. They can impose a speed limit as well.

[factotum]

I'm pretty sure if you can afford a car that will do 250km/h (155mph for those of an Imperial measurement persuasion) you can probably afford tyres capable of going that speed as well.

[Rogan]

Thats propably true.
Still, it's not common to drive at those speeds, even if you would be allowed to (and have a car capable of) going up to 250km/h

After all, you need a clear lane as well. And good weather, clear view and so on.
But it would be legal

[Peelee]

My contention there was that you trying to zipper without everyone else doing it can be creating a penalty for yourself, not avoiding one. You go all the way up to the merge point, and all the non-zipper people refuse to leave room for you, leaving you stuck waiting until you get lucky with an unusually courteous driver arriving in the other lane. The fact that you "tried to cut the line" may even make people who normally would have let you in decide not to, as punishment for your perceived offense.

This factor is, obviously, weighed against the time saved by using a nearly traffic-free lane for a bit, and where the balance on that lies depends heavily on the local driving culture. In some places, you'll be let in pretty promptly. In others, you may be forced to wait several minutes or more.

Ah. My bad! But yeah, I'm usually not too put off by it. Never had to wait more than a few car lengths.

I've lost track, is that fuel efficient, or time efficient?

Rule of thumb: never assume I'm fuel efficient. I love my hybrid, because I'm getting 1.5-2x the mileage my old car got, but it'd be even greater if I drove for fuel-efficiency. I dont. On a related note, I also love the beastly power my hybrid can have. Not as much as my old car, but not far off.

[spinningdice]

We get those all over the place (but with 60MPH limits). Our police have a policy of only reviewing the 'default' (60mph on roads with no pavement) if there is an accident on there, so in the rural area I live there's roads that you'd need a death-wish to drive at the speed limit on.

As I was recently drafted onto a road safety course to escape gaining points on my licence (I was doing 34 in a 30 zone fyi), they do iterate that speed limits are limits not targets and reminded that you can legally be fined for doing 1mph over the limit. The +5mph or +10%+2mph are complete myths. Apparently in Wales at least they are pretty draconian at enforcing this, less so in the rest of the country, but ubiquitous speed camera's are uncaring.

[Vinyadan]

Apparently in Wales at least they are pretty draconian at enforcing this

Well, it's even in their flag, isn't it? [/badjoke]

[Fiery Diamond]

We get those all over the place (but with 60MPH limits). Our police have a policy of only reviewing the 'default' (60mph on roads with no pavement) if there is an accident on there, so in the rural area I live there's roads that you'd need a death-wish to drive at the speed limit on.

As I was recently drafted onto a road safety course to escape gaining points on my licence (I was doing 34 in a 30 zone fyi), they do iterate that speed limits are limits not targets and reminded that you can legally be fined for doing 1mph over the limit. The +5mph or +10%+2mph are complete myths. Apparently in Wales at least they are pretty draconian at enforcing this, less so in the rest of the country, but ubiquitous speed camera's are uncaring.

It makes so much difference where you live. Where I live (which is in the USA) it's almost expected that you'll be driving 5 mph over the speed limit in some places.

[danzibr]

Huh. This thread makes me feel like a bit of a bad driver. I accelerate quite quickly to speed limit+4, then set cruise.

Even going 4 over, people always pass me.

[factotum]

While it's no excuse for always going to speed limit + 4, speedometers in cars almost invariably over-read--e.g. when your speedo is showing 75mph you're probably only doing 70. You can see the difference if you use a sat nav, because those generally measure your speed quite precisely (although the manufacturers invariably have a disclaimer that they're not liable if you're caught speeding when their satnav showed you were doing the correct speed).

[danzibr]

While it's no excuse for always going to speed limit + 4, speedometers in cars almost invariably over-read--e.g. when your speedo is showing 75mph you're probably only doing 70. You can see the difference if you use a sat nav, because those generally measure your speed quite precisely (although the manufacturers invariably have a disclaimer that they're not liable if you're caught speeding when their satnav showed you were doing the correct speed).

Thanks for the info!

Time to start going 6 over 8)

[The Fury]

Speaking only for myself, my car is old and is showing her age in a lot of ways. Going from idle to full throttle can actually cause the engine to die in the middle of the intersection. No fun for you, or for me. So accelerating up to the speed limit from a dead stop can be difficult, though it usually depends on what the speed limit actually is. 25-35 mph? Usually not a problem, unless it's uphill. 45 mph or more? I'd better use the slow lane.

While it's no excuse for always going to speed limit + 4, speedometers in cars almost invariably over-read--e.g. when your speedo is showing 75mph you're probably only doing 70. You can see the difference if you use a sat nav, because those generally measure your speed quite precisely (although the manufacturers invariably have a disclaimer that they're not liable if you're caught speeding when their satnav showed you were doing the correct speed).

According to the road signs that display your speed, the opposite is true for me. 45 on the speedo, usually mean closer to 50 mph in actual speed. Maybe it's just another side effect of previous owners' (mis)treatment of this particular car.

[Vinyadan]

According to the road signs that display your speed, the opposite is true for me. 45 on the speedo, usually mean closer to 50 mph in actual speed. Maybe it's just another side effect of previous owners' (mis)treatment of this particular car.

It could also mean that your speedo is right, and the signs overestimate your speed. A way to check this out, if you aren't alone in the car, is to ask your passenger to count the milestones (or whatever they use now to signal the mile or km of the road in which you are), and use the time needed to desume speed.

[Dewm]

Slow acceleration is more fuel efficient, lowers wear on the tires, and is considerably safer. Just because you are impatient does not obligate anybody else to be in a hurry.

Of course, that is coming from somebody who will slow down if somebody is tailgating me, so I have a bit of a bias.

Sometimes people are in a hurry. For example I often drive with Doordash and other food delivery serives, and I need to make it on time, otherwise my account will suffer, and sometimes the restaurant takes longer than expected. Sometimes I tailgate, but when you're in a hurry, it's hard not to. I get it, it's an ******* move, but you'll piss the person off even more when you pull that kind of ****. But then again I'm admittedly an aggressive and fast driver, so I have a bit a bias.

[jayem]

This doesn't really get into the "why" though. It just correlates those significantly below the speed limit with more accidents. You know what also correlates to going significantly below the speed limit? Nervous drivers (new) and/or old drivers. Somehow I think that would also be a pretty significant factor here.

You've also got two other issues:

How do they find out the speeds? Self reporting seems risky, I know I'd round down if I was in an incident. Whereas at other times I'd give my peak speed.

[already mentioned]
Safe driving speeds vary more than speed limits. If you have a region of 60mph national speed limit that includes a corner that (to actually have a decent stopping distance) should be taken at 40mph, but is actually taken at 50mph by most drivers (which is safe 99% of the time, cars rarely turn off). Then you'd get a similar effect, the driver can honestly report that they were going well under the speed limit. While the straight sections will boost the stats and give a false average speed.
Similarly with snow, etc...

[Evil DM Mark3]

Of course, that is coming from somebody who will slow down if somebody is tailgating me, so I have a bit of a bias.

That's actually required by the UK Highway Code. If someone is tailgating you should slow down to increase the gap (and thus reaction time) between you and the car in front so you have to break less hard if they stop suddenly, meaning you are less likely to get rear-ended.