What’s a little extra 5 or 10 mph on the clock?
People will always drive at the speed that feels safe, it’s not just Americans. Gradually here this is being recognized, and roads narrowed, speed bumps added, etc. in places where we need to go slowly. At my work complex the stated limit is 10 mph and even on my bike I am speeding, and cars are passing me, but it doesn’t feel unsafe at all.
There are roads where speeding is so common you will in fact be dangerously tailgated if you drive the speed limit
i have gotten tailgated by a semi truck in a highway construction zone, one of the scariest things i have experienced while driving. i couldnt even see his lights in my back window he was so close
My entire commute
In my experience, American roads are built to support much higher speeds than the speed limit is set. Going 10-20mph over the limit doesn’t feel particularly unsafe on the wide, straight roads.
On the other side, it felt crazy to drive the speed limit on (for example) the narrow, windy roads in Ireland. The limit there felt like a literal maximum, whereas in the US it feels like the minimum.
this is often not thought about when talking about this but even the spacing in the lines drawn on the road influences your perception of speed.
the solution isn’t trying to enforce lower limits, it’s having roads enforce them.
As noted car enthusiast NotJustBikes has said, driving is not a conscious activity. We drive to what feels right, to a degree. A road built to support 100kph will always have speeder problems until layers of traffic calming are put in place.
UK B road limits are in fact limits, often being little more than millennia old cart paths with asphalt applied
If you look at the design documents for the roads in your area, usually available in plain old PDF files at your State DOT website… it usually states both the designed speed, and what the posted speed will be.
If it’s a modern road, it is almost certainly designed for 5-10mph over what the posted limit will be. Because they know most traffic will speed, and that is accounted for in the road design, regardless of the posted limit sign.
It’s wild to me that someone heard this logic and said “makes sense”.
Like, I get it from an engineering perspective. You find out the maximum capacity of a bridge, account for extremes like multiple heavy loads, find the point of failure, and then engineer in a safety factor. Making sure your bridge can handle your theoretical maximum several times over.
But, we aren’t dealing with people seeing a strong bridge and thinking “nice, I can carry more stuff in my car” and encourage a larger capacity. The capacity they carry is already limited by their vehicle. They aren’t even thinking about the bridges capacity.
With road design. The road controls the capacity (speed) directly to the user of the road. There is a physical speed that if their car reaches they will crash. They interact with it directly.
Designing a road that increases that speed at which a guaranteed crash will happen is primarily just increasing the lethality of said crash. That’s the primary part of “safety” that the design guideline is controlling.
It’s saying. “Hey, if you go too fast for the road conditions, don’t worry. We made sure that the road was designed so that when you reach that speed you’ll have less time to react and more chance of dying”.
Also, “everyone speeds” is bull shit. Every speeds down a zero intersection straight road with a posted speed limit 15 MPH under what the road was designed for. It’s a fucking self fulfilling prophecy.
It’s saying. “Hey, if you go too fast for the road conditions, don’t worry. We made sure that the road was designed so that when you reach that speed you’ll have less time to react and more chance of dying”.
That’s not at all what’s being said. Knowing the speed people will want to drive with a specific design, doesn’t make it inherently “too fast”, its the exact opposite. The road designers are literally designing what the road condition will feel like to drivers, then taking the human factor into account to set a sensible limit instead of an arbitrary one.
If they know the road design will make people drive 50mph, and that most people drive 5mph over the posted limit, they post a 45mph limit. Driving at 50mph down that road is not “too fast”, that’s literally what was designed to feel correct.
There have been several studies over the years about posted versus real world speeds. Including studies of the same road with the posted speed being changed and monitoring driver behavior. They found that regardless of what the posted sign says, people usually drove about the same speed on that road. The minimum and maximum speeds varied with different signs as some people used that number directly, but the average of all traffic stayed the same regardless of the signage because that’s the speed that felt correct for that roadway. In some cases that was under the posted limit, in others that average was up to 10 over the posted limit.
Every speeds down a zero intersection straight road with a posted speed limit 15 MPH under what the road was designed for. It’s a fucking self fulfilling prophecy.
Most roads do not have posted speed limits that vary dramatically from the speed that feels right on that road, because they’re designed for a specific speed and posted with that consideration. Artificially low speed limits are not common. They’re usually from a speed being changed years after the road was designed and built, so it wasn’t intended to have drivers at that speed and also wasn’t physically changed to help reinforce that speed subconsciously, or from a town trying to boost ticket revenue.
When I was in Appalachia, on the mountain roads, many are very narrow, and winding. Speed limits often like 40, and you can’t go more than that without crashing unless you have a motorcycle or something. It’s not a suggestion, it’s the maximum you can do on the curves.
Furthermore, even though that’s the maximum, the safest speed on mountain roads is the one you feel comfortable with. Even though I’m experienced driving in the mountains and can comfortably go that limit I’m not gonna be too annoyed at the car from Florida in front of me going 15mph under. I will get extremely annoyed when they don’t use the pull out spots or accelerate up to the speed limit on the passing zones though.
I would agree with the several comments on the engineering and design of the higher speed roads being able to handle increased limits, but I don’t think the road or even most of the cars’ ability to go that fast are the problem. It’s the drivers. Raising the limits means people will go that much faster (the ones who are even bothering to stay close to it), and the risks will be higher and more deadly.
There is also the issue of fuel efficiency vs. speed and how little time is gained for a lot more gas used. Even with modern cars there’s a limit of aerodynamics and how much more it takes to push air out of the way faster as you get higher in speed. Of course this pales compared to how many people I see idling in parking lots on their phone, and then complain about gas prices. There’s a disconnect somewhere.
During the Arab Oil Embargo they lowered speed limits on highways to 50 mph, which is the most economical speed to drive.
Windows up is more efficient also, as is fully inflated tires.
I tested my car as a hypermiler over thousands of miles on dead flat roads empty of other vehicles, my daily commute was 78miles. The most economical speed was 30mph in 5th gear with cruise control on. For most people that’s not a practical speed for any kind of long journey,but I was getting over 100miles per uk gallon in the summer (hot weather helps with fuel economy, as does not having headlights or ac on). I got through so many audiobooks driving so slowly!
If you don’t mind sharing, what car is that, and what year of manufacture?
Economy isn’t just about fuel economy. Less unsprung weight and highly inflated tyres reduce fuel consumption, but low profile tyres result in damaged wheel rims and lack of adhesion results in lack of control.
Alloy wheels with low profile tyres are lighter, but are also more prone to irreparable damage.
If you have the smallest steel rims that fit over your brakes (and the highest profile tyres to match manufacturer recommendations), you are less likely to have a puncture or damaged wheel, especially in potholed regions. (I live in Victoria, Australia).
If you have the correct tyres inflated to the correct pressures, they will last longer and provide the most optimal grip.
which is the most economical speed to drive.
That is not universally accurate. Even at the time, there were vehicles that were more efficient at higher speeds than 55mph. But those weren’t American designs, of course so they were of course ignored in favor of the general majority. And those vehicles that were more efficient at higher speeds, got screwed for simplicity.
I did wonder about that actually, questioned it.
It seems odd wind resistance would be higher at higher speeds and not linear to me as well. Idk why but it’s counterintuitive to me.
Drag is not linear, it is proportional to the velocity squared.
However that is only one of the big factors. Vehicle shape and aerodynamics have a large effect on drag. This is one of the reasons for the flush door handles on some vehicles, lowered drag means increased efficiency. Then you also have the efficiency of the engine and power train at various speeds and power output.
many of the speeders could well be cops who don’t feel like enforcing traffic laws &, well, prefer to speed themselves
You can add rural Japanese drivers to that. “Customary” is about 10kph over with some going 19 just to stay safely under one of the higher penalty tiers. I don’t just mean on the expressways, I mean on rural roads marked 30-50.
Because roads are engineered to accommodate a certain speed limit then politicians artificially lower it so they can show how safety conscious they are. Then instead of admitting it was a stupid rule they blame everyone for breaking it just like they do with abstinence only education.
It’s because it is never enforced anymore.
It’s worse than that. If everyone speeds all the time, cops have a valid reason to pull over and harass anyone they choose, on the pretext of speeding. You’ll never guess what demographic gets a disproportionate amount of police attention despite not speeding (or committing other traffic violations) significantly more than average.
And of you’re not speeding, it appears in the US they stop you for endangering others on the road
So they set up speed camera(that is not Flock or mass surveillance) and people yell about constitutional right.
deleted by creator
I mean, going the speed of traffic is safer than not. So yeah, it’s okay when everyone else is doing it.
Bullshit. It’s the same mentality as people had during COVID. “The others aren’t wearing a mask, so neither should I”
Bullshit. With covid if I wear a mask and you don’t there’s still been a significant decrease in risk of transference and both of us are safety. With not going the speed of traffic, if I strictly follow the speed limit and you don’t there exists a differential that increases our risk equally.
Speed limits are one of very few, if not the only, legal limits that is set by observation of actual human behavior. Look into how the 85th percentile rule is used (in the US). If a speed limit is set too high or too low compared to nominal human behavior the state creates a difference in perceived safe speed and strict adherents. It is that difference that causes problems.
There are parts of Atlanta where the speed limit is dynamically set (sometimes down to 40mph) and the flow of traffic is maintained at 20-30 miles faster; there are also parts of Florida where the speed limit is 70mph and the flow of traffic is 80-85mph. In each case, a strict adherence to the posted limit is dangerous as you now become an obstacle everyone else needs to evade.
The inverse is also true. If there are adverse conditions on the road that warrant the flow of traffic to 30mph under then going the posted limit you also put yourself and those around you in significantly higher risk.
If you’re traveling at the posted speed limit and there’s a broken down car stopped in front of you, do you strictly adhere to the posted limits straight into an accident or do you adjust your speed to that of the flow of traffic in accordance with the conditions of the road?
Traveling with the flow of traffic makes you more predictable and puts you inline with the actual realized conditions of the road, and being predictable on the road is the safest thing you can do while driving.
Wearing a mask makes everyone safer. Speeding along side a multitude of other speeders makes all of you safer.
Also if the law enforcement in the area lets it happen, what message is that supposed to send to your average single-loop thinker?
Laws that aren’t enforced are Laws that can be enforced selectively.
Right you are. It’s part of the perennial conservative system of control: There’s an in-group the law protects but doesn’t bind, and an out-group the law binds but doesn’t protect.
Right. Traffic enforcement that’s “random” is fundamentally unjust. But conservatives like it because they can bully the out-groups, and some assholes like it because it brings money in via fines.
Let’s it happen? I regularly see the police where I live do the kinds of things they pull people over for; speeding, rolling stops, distracted driving, failure to signal etc.
Tough to maintain credibility when those charged with enforcement don’t follow the rules either.
That’s true where I live too, but the asshole drivers not in cop cars far outnumber the entire police force of my town. Every day I see someone run a red light, change lanes in front of someone without signaling, or do 35 in a 25 school zone. And they think that’s okay not because they saw a cop do it too, but because they see all the people around them getting away with it. The cops either don’t care or are too busy blowing their budget on nice gear to hire enough people to do the job.
deleted by creator
It bothers me when people don’t go the speed limit. Faster or slower, the speed limit is to set a consistent speed. Consistent means predictable which results in safer conditions. This would result in less traffic and less fuel consumption.
However, following the flow of traffic is safer than trying to go the speed limit. If you’re the one person going 20 units per hour slower than everyone, you are the hazard.
However, following the flow of traffic is safer than trying to go the speed limit. If you’re the one person going 20 units per hour slower than everyone, you are the hazard.
If people are intent on breaking the law, I will accommodate them passing me safely.
I will not be breaking the law to accommodate someone else’s desire to do so, to consider that to be an expectation is downright delusional
Yeah but am I going to put myself at risk of a ticket, points on the license and higher insurance rates, and attention from the police, (the less interaction the better,) because others speeding is making it dangerous?
Sometimes. Most of the time, I follow the law. Almost all of it. Only in passing really do I speed on purpose even a bit. I would for safety if it was needed, but I am not going to put myself in danger of being pulled over because people that are less likely to get hassled by the cops are mildly inconvenienced by someone going the speed their lawmakers all agree on.
In an ideal world, I agree 100%. Most of the time I can set my cruise to the speed limit and let the reckless people pass.
I don’t. I go the speed limit to the best of my ability. I only speed by accident and when safety suggests I need to follow traffic.
Often it occurs because the speed is poorly done. Engineers will come out and review road shape, surrounds, etc. and agree to new limits if it’s clear drivers are, on average, using the road at the speed anyway.
But that’s a big difference from a culture of people just speeding everywhere.
Honestly, even if you raise limits, people will raise them further
Just like not stopping at stap signs…
