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Comment by Roritharr | Hacker News Reader

I'm really interested in the topspeed.

For german customers all the current gen EVs(Bolt/i3/Leaf/Ioniq) with a topspeed of 140-150km/h are to my opinion not really save to drive on the Autobahn as you don't have some speed buffer to overtake someone who's driving 120-130km/h fast enough.

If Tesla manages to give the Model 3 a top-speed of 200km/h that would be a game-changer and make it a viable car for me. The Model S is viable in that regard, just too expensive for me personally.

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As many people seem to take issue with my statement that I find it less safe if I don't have the option to overtake quickly someone who is doing 120-130km/h, i'd like to describe a situation which I notice at least once a week on the Autobahn:

I'm going 130-150 in the center lane, normal traffic flow speed. Someone in front of me in the center lane goes 130, but drives rather unsafely, serves to the left and right, brakes hard, is clearly not used to driving on the autobahn or their car (usually 90s or early 2000s small hatchbacks like a Ford Fiesta) is at the limits of what it can do. I'm behind that car and deem it unsafe to drive behind someone like that for longer periods of time, so intend to overtake. If the driver in front of me goes somewhere between 130-140km/h which is usually the case as this is the topspeed ceiling for many 45PS small hatchbacks, i HAVE to drive somewhere between 150-180km/h to quickly overtake that car without sitting too long on the left lane. The problem gets worse when the car in front has truck pulling out in front of him because the truck wants to overtake another truck, with a 10km/h difference because its uphill (a blood boiling situation for many experienced Autobahn driver).

Because the acceleration of the small hatchback is rather slow, many drivers of such cars want to conserve momentum, so they change lanes very quickly in such situations, where they suddenly are driving 120-130km/h on the left lane, where cars are shooting by at 180-220km/h which are then breaking rapidly, sometimes on the level of emergency breaking. EVs, having physics on their side, could have much greater acceleration, making that split second decision those drivers take favor the safer option in the future.

I see this too often to not care about it, and have driven one of those small hatchbacks myself when I was younger.

And well, the Autopilot is a great feature, but I'm not yet willing to bet my families life on it for longer stretches than i'm focused. Having tested it on the Autobahn, I found it hard after a while to keep the focus on the same level as I would have it driving myself.

I had to convert units to miles per hour to get a handle on the situation. For others in my boat:

You're going 80-93 mph in the center lane, and the unsafe driver impeding you is going 80 mph. In order to overtake this erratic driver, you need to move to the left lane and accelerate to 93-110 mph. The trouble is, on the Autobahn, drivers in the left lane are usually traveling at speeds of 110-137 mph, and often times even higher, up to 200 mph.

With those numbers in mind, I can entirely see your point. Early morning traffic in Dallas flows at 80-85 mph in the left lane. People don't always treat the left lane as a "fast lane" or a "passing lane." Some people cruise at 50 mph without a care for the speed of traffic around them. In order to merged into traffic in the middle lane while rapidly approaching the dangerously slow car in front of me, I sometimes have to accelerate to 90-100 mph.

I was reading a traffic study that showed that the single factor that contributes the most to traffic accidents is delta-speed. That is, the |relative speed| of the vehicle in comparison to the average speed of traffic. If traffic is flowing at 75 mph, a car traveling at 85 mph (10 delta) is less dangerous that a car traveling at 50 mph (25 delta). My anecdotal evidence confirms this. Slow drivers are often scared, timid, inexperienced, oblivious, and unpredictable. They'll change lanes without regard for the speed of anyone around them. They cause faster drivers to rapidly change lanes around them. They cause road rage incidents and reckless driving.

Anyway, I went off on a tangent, but I agree with what you're saying.

I believe you have a slight conversion error. I don't think you're seeing speeds of 200mph. (that would be 320+ kph!)

Yes, 320km/h is a rare sight. Happens though, a Veyron once blew past me while i was going 180 in the center lane at night. It felt like I was standing still.

The Autobahn sure sounds fun. Around here, if you do more than 145km/h they'll put you in jail.

No, the 180-200 mph was an observation that I added. I've seen Mercedes AMGs, M3s, M5s, RS6 Avants, R8s, Porsche Turbos, Ferraris, Lamborghinis, motorcycles, and similar performance vehicles doing 180-200 mph on the Autobahn. In person and in videos posted to forums.

I don't get it. I used to drive a Mercedes 200D (W123) for some years, and 112 km/h was my preferred speed. Overtaking a truck does take some planning if I don't want to be an obstacle on the left lane, but you know, at that speed I had a lot of time to plan :-)

(For the others: that car is from 1978 or so; I had two models, one with 55 hp and one with 60 hp, both Diesel. The car is ridulously heavy at 1.8 tons or so, and so you really don't want to be in a position where you have to accelerate quickly -- it just can't do it.)

I hate to break it to you, but if you enter the left-most lane of the autobahn doing 112 km/h, you DO NOT have enough time to plan. There could be a vehicle doing 250 km/h overtaking you in the left lane, behind a curve, and you wouldn't even see them until they rear-ended you doing 2x your speed...

Don't drive 250km/h if you cannot see the traffic ahead. It's a public road.

No speed limit != no responsibility.

It's the autobahn.

Elementary traffic rules still apply, and driving far above the "recommended speed" ("Richtgeschwindigkeit") of 130km/h puts extra burden of care on you. You have to expect people driving speeds around that.

Sure, but that thinking won't help you if you're the guy that someone crashes into because you can't go faster on the left lane... You might be in the right, but I'd wager the mortician won't care.

I really liked going 112 km/h with that 200D, but I also had faster cars. 200 km/h is my personal speed limit: the car might be able to go faster, but I can't.

It's the responsibility of the fast driver to make sure they don't crash into anything. And if the road (autobahn) has a curve in it and I can't see far enough, I have to slow down.

So when I'm the slow guy, it's my responsibility to look in the rear mirror to see if there is a car coming from behind, and if there is, of course I don't switch to the left lane.

I would also avoid switching to the left lane just behind a curve. But there is also great responsibility on the fast driver to make sure that they are able to stop.

As far as I know, not that many accidents on the autobahn where the fast driver rear-ends the slow one.

been safely driving a van with 140km/h top-speed on the autobahn just fine for years - there might be a correlation between the maximum speed of a car and the owners inability to drive safely, but the explanation is probably more a psychological than a technical one ..

your mindset is quite common among german car makers though, maybe the reason they are unable to offer competitive answers to a technologically rather boring challenge - bringing down the price for electronic vehicles by mass production

I have spent a lot of time driving a van with similar speed limitations around Germany as well. I agree completely. While it was frustrating as an American growing up hearing about the autobahn, it was still faster than I would drive in America.

It would only be unsafe if you attempted to pass people inappropriately (and spent too much time in the left lane). This is a driver issue, not a car issue.

As someone that loves to drive fast (hell, I am forced to drive a Prius right now and 195km/h is the norm, where possible), I have to agree with bemused.

If you can't do 100 reliably (I drove a lot of Citroen 2CVs) the Autobahn sucks, because now busses and some trucks try to overtake you.

If you can do 120 you're fine. You might not be fast and probably stay on the right/middle lane, but there is absolutely nothing wrong with that speed.

EVs have boatloads of torque available, so they can generally propel you near the top speed in reasonable time before it plateaus, and more often than not the problem isn't so much on the mechanical power side of things but on the electrical power storage and delivery one (heat, battery wear). So it's entirely unlike a 2CV which can't go fast and can't go halfway near top speed quick because the two values are directly tied to mechanical power delivery. An EV with a 145kph top speed says nigh about its acceleration profile.

EVs have boatloads of torque at low speeds. The challenge with Teslas on the autobahn is that they have one gear, which reduces their top speed and torque at high speeds compared to a multi-gear transmission.

Well that really depends how you drive / how the cars accelerate. I've experienced being on the autobahn and not being able to overtake because I can't accelerate fast enough (turbocharger on my car had broken, pedal to the floor and was only managing 120-130). I wouldn't however class it as dangerous. I find acceleration perhaps more important as the car has to be able to speed up enough to merge onto the autobahn safely before the merge lane comes to an end.

When you just have to say 'My car can only do 120-130 so I will only drive 120-130'. 130km/h is also the 'recommended top speed' for the autobahn so these cars should really have no problem.

I won't disagree that in the reasonably priced EVs you're not going to be speeding down the left lane overtaking everyone. For that you need a Model S / Model X / i8 at the moment.

Even if you aren't the sort to accelerate heavily most of the time, it's useful to have the ability. I've been in a handful of situations where quick acceleration has saved me from a potentially fatal outcome. Both instances involved things falling from flatbed trailers that would gone through my windshield like a hot knife through butter. One was a large poly storage tank whose strap broke, bouncing off the trailer and into traffic before going off the side of a bridge (it was surprisingly bouncy); the other involved square steel tubes that weren't secured in a niche under the trailer. They slid out the side as I was overtaking the truck at the end of a gradual turn on the interstate just as I was coming beside them. In both instances, because of how things played out, slowing--the normal impulse--would have likely put me right smack in their way.

Stupid truck operators who don't know how to secure things aside, even in normal traffic it's useful. Just look at most on-ramps in the US compared to on the autobahn. Even most of the longer ones can require quick acceleration to safely merge. Especially in traffic. I still remember my first trip to LA and the shit rental car I had the "pleasure" of driving. Had I gotten out and pushed, I'd probably have gotten up to the speed of traffic faster. That said, the Model 3 at a 5.6 second 0-60 time is above average. It might not be a match for the higher-end Model S variants, but most people won't have any issues with it.

I'm confident that it will go 200km/h - but you will run out of battery quite fast at those speeds (in much less than an hour), as it's obviously a lot less efficient.

Square power law applies to speed when air friction is factored in. It takes 2.37 times as much horsepower to go 200km/h versus 130km/h.

And then you have to cool everything, and generate more down force, which will take more energy.

Do you really need to overtake someone doing 130 km?

On the Autobahn.. Yes.

Why?

Do you have a limited amount of time you can stay in the autobahn as opposed to a French or Spanish motorway, forcing you to speed up?

Or is it that you just want to go 200Km/h and it's not about overtaking safely?

No its about following the rest of the traffic. In the unlimited sections, traffic is 130++ km/h (up to 200-250 in overtaking lane), So if you are slower, changing lanes, overtaking etc. becomes less safe.

You can just stay in the slow lane if that's a problem. And doing 130 km/h in the middle lane is perfectly acceptable, people can just overtake you by using the fast lane.

I've never had the problem OP mentions, on the Autobahn...

One thing I noticed last year when driving in France for the first time, compared to the UK was that there was a much greater difference in speed between the lanes. I imagine the difference would be even greater on the Autobahn. In the UK, the motorways have a speed limit of 70mph, and most people actually do it - very large vehicles are limited to 60mph. So emerging from the left lane to go around something slow only involves adding 10mph or so. In France, the right lane is often limited by a lorry going at 90km/h, while the left lane is at 130km/h. Emerging to go around something (if you have the misfortune of having to slow down behind the lorry because the left lane is busy) involves adding 40km/h to your speed before the next car in the left lane catches up, which involves a lot more power to do safely.

> In the UK, the motorways have a speed limit of 70mph, and most people actually do it

Are you kidding? Try doing 70mph in the third lane of a non-busy motorway and see how long it takes someone too be dangerously close behind you.

That's something different. Of course there are loads of people speeding too.

One other thing I notice is that different motorways in the UK have different characters. On some, yes people do tend to stick to the limit, and on others not so much. I haven't spotted a correlation yet with the locations of speed cameras.

But you were talking about overtaking, that's a completely different scenario (keeping up with traffic on the slow lane).

You're saying that any combination of car and driver than can't sustain cruise speeds over 130Km/h is a danger.

You don't have to but some people like to arrive earlier and drive faster. And many people I know don't like following other cars, so they'd rather overtake and drive 130 km/h in front of the other car than behind. This, however, changes with autopilot.

Driving faster on the autobahn (or any freeway/highway) will not get you to your destination much faster. The total transit time is impacted the most by city/local traffic and such. Unless you are on a 500km journey you are not saving much time going 180 (rather than 140) on the autobahn.

This is actually incorrect. When you ask a German how far away another city is, their first question will be: "What kind of car do you drive?"

The biggest difference is that in Germany, the speeds are more sustained. In the US, cars generally drive in whatever lane they feel like, so your speed is constantly changing. So even a difference of 180 vs 140 will be significant. (and it could easily be 200 instead of 120).

This is untrue. Are you seriously attempting to use a colloquial joke as some sort of evidence?

While Germans are a bit more conscious of driving in the left lane when not passing, what you are saying neither makes sense, nor is it applicable, especially in any amount of traffic.

It also totally discounts the vast amount of road construction and maintenance that Germans continually do on their roadways (infrastructure maintenance is a big deal). The construction alone, especially in Hessen/Rhineland Pfalz vastly impacts travel times in ways going 40kmph faster could never attempt to approach.

I've driven plenty in both the US and Germany and the road etiquette in Germany is light years ahead of the US.

If I choose to drive 120/130 on the autobahn I have a much higher chance of doing so continually than if I choose to drive 75 Mph on an Interstate highway in the US.

I'll give you my anecdotal evidence from last year's trip to Germany. I took a ~550 km trip, and while I don't have actual GPS data from my trip on hand, I do remember that I was able to drive roughly one third of the way in sections with no speed limit and no traffic/construction.

For 2/3 of the way my average speed (including traffic and construction) was 122, so that took 3 hours. For the rest (1/3) of the way I was able to travel with unlimited speed. Traveling 183 km at 183 km/h (average) vs. 122 km/h saved 30 minutes of my trip.

I'm absolutely relying on anecdotal evidence. But I spent more than a decade on tour with a band driving vans all over the US and Europe. I've been on almost every stretch of highway in Germany and America many, many times, and I was extremely familiar with travel times between cities in all seasons and conditions. So yes, still anecdotal evidence, but a whole lot of experience behind it.

Obviously construction (anywhere) affects travel time. But in the US the highways have more exits, cops running radar, and there's ALWAYS someone going slowly in the left lane. Unless you're in the western desert states, it's pretty hard to maintain a steady speed. By contrast, everyone in Germany knows how to drive, and everyone follows the rules about keeping right and passing left.

Wait, I'm not with the GP and don't think you NEED to overtake people at 130.. Why would you?

But I don't think you can't overtake safely and be fast. It depends on the situation and is, in my opinion, quite common. Most people drive sane, 130 or 200.

No, at least not for me: My plan is buying the Model 3 and then engaging the autopilot in such a case - and just travel behind whoever is driving with 130 km/h in front of me.

So for me - a reliable autopilot for the Autobahn is much more important than the top speed.

Do you want to die?! Do not use the Tesla autopilot unless you are in a medical emergency and cant operate the vehicle.

My reply has been downvoted to oblivion. Let me try again.

1. Tesla autopilot has a disengage rate of 182 in 550 miles. This cannot be safe in anyway for any kind of driving http://blog.caranddriver.com/in-the-self-driving-race-waymo-...

2. Apart from the fatalities there have been many other accidents with Tesla https://arstechnica.com/cars/2016/05/another-driver-says-tes...

http://grist.org/business-technology/whats-the-point-of-self...

3. https://www.theguardian.com/technology/2017/apr/03/the-custo...

4. Check YouTube for any number of autopilot crashes

On the Trans-Canada - yes, absolutely. The limit on large stretches of it is 120, and in good conditions, traffic moves at 135-140.

> Model S is viable in that regard, just too expensive

Wow, even the 2nd-hand price for a Model S in DE is €60k. I wonder why are they all Pxx models?

https://www.tesla.com/de_DE/preowned?model=ms&sort=price|asc...

What are you comparing it to? In contrary, German cars in the US are expensive. My co-workers in the US would not believe that in Europe a German car such as BMW or Mercedes is commonly the first car of many young men have.

> What are you comparing it to?

List price.

I'm not sure it's that common to have as a first car is it?

Not a new one of course, but the ones in the 2000€ price range. Those do come with problems, but my friends were eager to fix them. Still, from around dozen of my friends who did purchase a car after getting a license, around ten ended up buying BMW, VW or Mercedes. As far as I can tell the reason was availability of replacement parts.

Germany is not some mythical land of cheap fast cars. We have the same 10 year old 3 series with 80k miles on the clock for $5000 here, too. But maybe we just are also aware that the most expensive German car in the world is a cheap one.

The top speed of the 60 kWh model S is 210 km/h, and the model 3 should have a battery of 50-55 kWh. If it were a model S, that would put it's top speed at 195-203 km/h, but the model 3 is smaller and lighter, so the stop speed should be close to 210 km/h.

The Model S60 is software limited to 210 km/h. The S75 with the exact same battery has 230 km/h as top speed.

The low end Model 3 battery pack according to Teslarati will be 60 kWh. But even with 55 kWh it should achieve 210 km/h.

http://www.teslarati.com/tesla-model-3-battery-pack-216m-mod...

I think the ability to accelerate faster compensates in part for lacking top speed (in some other situations).

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