What speeds are you dreaming of, realistically?

[Mono]

For context, this is the needed power vs speed graph when only taking into account air drag with a frontal area of one square meter (standing):

Roughly 100W at 20km/h,  820W at 40km/h, 2.8kW at 60km/h, and 6.6kW at 80km/h:

Edited December 5, 2019 by Mono

[atdlzpae]

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legalization and enforcement of legality, what maximum speed do you want to be able to ride

Since the question is about the law, the answer is > 70km/h. If someone wants to ride with cars, they should be able to do so without any restrictions.

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How fast do you want to go, realistically?

I almost never pass 30km/h.

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For context, this is the needed power vs speed graph when only taking into account air drag with a frontal area of one square meter

Winds of 40km/h happen from time to time, so it's theoretically possible to ride at 80km/h with only 820W of power.

Edited December 5, 2019 by atdlzpae

[Mono]

1 hour ago, atdlzpae said:

If someone wants to ride with cars, they should be able to do so without any restrictions.

Do you mean without drivers license and insurance on motorways with >70km/h speed limit?

1 hour ago, atdlzpae said:

Since the question is about the law

The question is not about the law, but about what you would want or what you think other people want, considering the real world (and not a dream world without physical limitation or laws).

Edited December 5, 2019 by Mono

[scotchtape]

If you can ride "fast", it's really not that hard to go really "fast" on straightways / semi highways.  

Obviously depending on what you have around you, couple of roads we have available that can be relatively free of traffic, speed limit around 80, with a large shoulder for bicycles.

I find it fun once in a while, geared up, just booting it on the MSX I hit the beeps too easily, so a nice bump in speed would be nice.  I think some people freak out at higher speeds so they assume no one can ride it safely, but they probably don't have the nice, long stretches of road to ride on.

[atdlzpae]

1 hour ago, Mono said:

The question is not about the law, but about what you would want or what you think other people want, considering the real world (and not a dream world without physical limitation or laws).

Oh, ok then. ;-)

In that case in traffic, respect the same limitations as cars. If your unicycle can go 80km/h and the speed limit is 80km/h, it makes no sense to limit that. I fully respect the right of a person to kill themselves. Maybe a drivers license cat. A could be required... IDK.

In the bicycle lane, some sensible limit, like 30km/h. But it has to be for all vehicles, bikes included.

[musk]

For me the maximum speed = reserve power.  I want to ride at 30kph, but I want to do it on a wheel that's capable of 45kph for safety reasons.   If there's a large bump in the road while I'm accelerating from 25-30kph, I want to know that the wheel can handle the spike in power.

Manufacturers could keep the buffer amount a secret and artificially limit the top speed, but that's probably not in the economic interest for the manufacturer.  It also doesn't inform the user of what kind of buffer is really available.

Give me a 60kph wheel and I'll still ride 30kph.   Remember, safety gear can help you slide and reduce some impacts, but if you hit a metal pole at a fast speed it will hurt, and might change your life in a bad way.

 

 

Edited December 5, 2019 by musk

[Aneta]

1 hour ago, musk said:

Give me a 60kph wheel and I'll still ride 30kph.

I'm exactly the same - 50kph wheel, but I limit myself to 25kph. I want a 500kph wheel, to still ride it at 25kph - the torque will be virtually constant in my speed range!

[Mono]

On 12/5/2019 at 11:29 PM, Aneta said:

I want a 500kph wheel, to still ride it at 25kph

You don't want a 500kph wheel, because this would weigh far above 100kg.

EDIT: 500kph needs 1600kW power (1.6 million Watt) to overcome the drag and the lightest electric motor delivers 10kW per kg peak power, so we are closer to 200kg than 100kg. EUC motors are currently more at 1/2kW per kg, meaning 20 times heavier meaning 2000kg for 500kph.

https://en.wikipedia.org/wiki/Power-to-weight_ratio#Electric_motors_and_electromotive_generators

Edited December 7, 2019 by Mono

[Mono]

2 hours ago, musk said:

For me the maximum speed = reserve power. 

I can see that. The reason is that we don't have (yet) any other and more reasonable established way to determine reserve power. More maximum speed does not even necessarily mean more reserve power. The values of maximum thrust at 10, 20, 30,...km/h would be much better and quite feasible.

[Mono]

Remarkable: not a single vote (of 2x18) for a wheel that would be legal in many European countries, where the legal speed limit is either 20km/h or 25km/h.

Edited December 7, 2019 by Mono

[Aneta]

On 12/5/2019 at 2:47 PM, Mono said:

You don't want a 500kph wheel, because this would weigh far above 100kg.

EDIT: 500kph needs 1600kW power (1.6 million Watt) to overcome the drag and the lightest electric motor delivers 10kW per kg peak power, so we are closer to 200kg than 100kg. EUC motors are currently more at 1/2kW per kg, meaning 20 times heavier meaning 2000kg for 500kph.

https://en.wikipedia.org/wiki/Power-to-weight_ratio#Electric_motors_and_electromotive_generators

I was just using 500kph figuratively, to get the point across that even for intentionally-slow riders, ever faster wheels do have benefits.

500kph segwheel with reasonable weight is impossible in principle, even if they invented a motor with infinite power per kg, simply because the aerodynamic drag at this speed will be like 5 times the rider's weight, so it would require coefficient of friction of 5, which is impossible. If the wheel weighs 2000kg, however... hmm... something like this maybe?

[Mono]

2 hours ago, Aneta said:

500kph segwheel with reasonable weight is impossible in principle, even if they invented a motor with infinite power per kg, simply because the aerodynamic drag at this speed will be like 5 times the rider's weight, so it would require coefficient of friction of 5, which is impossible.

The standard solution for this "impossibility" is to have a spoiler. Shaping the aerodynamics becomes quite relevant at high speed. However you didn't want to go 500kph, you wrote "I want a 500kph wheel, to still ride it at 25kph".

In any case, the main point we can learn here is that more is not generally better, not even approximately.

[LanghamP]

On 12/7/2019 at 5:00 AM, Mono said:

Remarkable: not a single vote (of 2x18) for a wheel that would be legal in many European countries, where the legal speed limit is either 20km/h or 25km/h.

I'm entirely for such a speed limit, in fact, I would LOVE a 20 to 25 km/h speed limit that applies to ALL vehicles within an urban area. And not a stupid speed limit sign, but a mandatory smart governor that stops vehicles from exceeding those limits.

But we just have those mandatories applies to eVehicles, then wonder why no one didn't vote for that option? You don't say?!

In the words of my dearly beloved and departed 2 pack a day Catholic Irish grandmother whenever confronted by people she didn't approve of...

[atdlzpae]

40 minutes ago, LanghamP said:

And not a stupid speed limit sign, but a mandatory smart governor that stops vehicles from exceeding those limits.

It wouldn't help. We already have this in Poland for electric bicycles and pretty much everybody is removing the limitation.
The only way to do it fairly is to set up speed cameras.

[Coffee guy]

That is one badass looking ride in the photo !   😨

[LanghamP]

45 minutes ago, atdlzpae said:

It wouldn't help. We already have this in Poland for electric bicycles and pretty much everybody is removing the limitation.
The only way to do it fairly is to set up speed cameras.

I said all vehicles. Ridiculous to limit bicycles to 20 while drivers go 150...

[atdlzpae]

@LanghamP You said "mandatory smart governor that stops vehicles from exceeding those limits".
I understood it as "A device that limits the speed of a vehicle". That's what I'm against. It's almost unenforceable.

[Mono]

33 minutes ago, atdlzpae said:

@LanghamP You said "mandatory smart governor that stops vehicles from exceeding those limits".
I understood it as "A device that limits the speed of a vehicle". That's what I'm against. It's almost unenforceable.

I agree that laws should be enforceable to be meaningful. I don't agree that type-related speed limits for vehicles are particularly difficult to enforce, if this is so desired. I believe we do that for heavy trucks already pretty effectively.

Speed limits can also be enforced by investigating vehicles that are suspicious and seizing them when found to be manipulated. Maybe that's not how it works in Poland, but that happens, to all I know, regularly in Germany. Even speed measurements are much easier to do in this case, because they do not need to prove the offence, they just need to deliver the initial suspicion to investigate the vehicle. So a few small drones flying around following speed offenders would already be pretty effective and almost ridiculously cheap. I don't think that people would like such drones, they probably prefer to die on the streets, so this probably won't happen any time soon.

Another way to enforce speed laws once and for all is to require vehicles to communicate their position data. That is likely to happen sooner or later anyway, because it would and will bring vehicle vs vehicle crashes to pretty much zero. I would consider this to be overkill for PLEVs though.

It is also possible to require that any manipulations will stop the vehicle to work.

Nothing can prevent each and every single person from breaking the law, of course.

[litewave]

2 hours ago, Coffee guy said:

That is one badass looking ride in the photo !   😨

Definitely provocative and sexually suggestive. Pandering for upvotes to a 98% male audience? Nah, we're all too mature for that. 

[PLEASE_DELETE]

Deleted.

Edited March 18 by PLEASE_DELETE

[Ben Kim]

I want 80 kmh. Will it happen on an EUC? Only Gotway would have the stones to do that 

[Aneta]

34 minutes ago, /Dev/Null said:

I'm pretty happy at 20-30km/h.  I"m moving way faster than walking & can have reasonable fun w/o fearing too much that I'm going to die instantly should the wheel give out.

I'm with @Aneta on this.  Looking forward to buying something bigger than my V10 with more battery & more reserve power to continue to ride at 20-30km/h

To expand on this, my hard limit of 25kph is not only to have an ample reserve of thrust margin, but to respect the limits of our bodies. In case of head-on impact of your head in helmet or any part of your body with an obstacle, the stopping distance is proportional to the square of speed. Say, if at 25kph the foam in your helmet is penetrated or compressed by an obstacle by 1inch and does not reach your skull, at 50kph it will penetrate 4 inches and will crack your melon open. We often ride in environments with lots of obstacles very near our paths, like light poles, fences, curbs, trees, cars, etc. This is very different from, for example, motorcycles on highway. Consider this recent example where a rider got almost impaled by fence, what saved him was not only gear, but slow speed. Imagine hitting those metal rods at 50kph...

 

 

[atdlzpae]

12 hours ago, Mono said:

I agree that laws should be enforceable to be meaningful. I don't agree that type-related speed limits for vehicles are particularly difficult to enforce, if this is so desired. I believe we do that for heavy trucks already pretty effectively.

That's because every single truck has to pass the yearly test. And a truck is not a good form factor for racing.
Do you want to have your e-bike checked for compliance every year?

12 hours ago, Mono said:

Speed limits can also be enforced by investigating vehicles that are suspicious and seizing them when found to be manipulated. Maybe that's not how it works in Poland, but that happens, to all I know, regularly in Germany. Even speed measurements are much easier to do in this case, because they do not need to prove the offence, they just need to deliver the initial suspicion to investigate the vehicle.

That's how it works for cars and trucks. And I like that. But I hope they don't implement a similar solution to PEV's.
Germany is not a good example to quote because they are way too strict in their regulations (Ordnung muss sein) and getting an EUC legalized there is close to impossible.

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So a few small drones flying around following speed offenders would already be pretty effective and almost ridiculously cheap. I don't think that people would like such drones, they probably prefer to die on the streets, so this probably won't happen any time soon.

But how do you identify the rider? Do you require them to register their vehicle and install plates? I don't like authoritarianism and such solutions almost certainly will make EUC's illegal.
Germany proved that. It's legal if you insure your EUC. But nobody will insure your EUC. Also, people who come to Germany for 2 weeks certainly will have to leave their EUC's at home, too much bureaucracy.

12 hours ago, Mono said:

It is also possible to require that any manipulations will stop the vehicle to work.

No, it's not possible. I hope I won't have to argue with you about that.

Edited December 9, 2019 by atdlzpae

[LanghamP]

3 hours ago, Mono said:

Speed limits can also be enforced by investigating vehicles that are suspicious and seizing them when found to be manipulated.

If the high technology solution is unappealing, then I recommend the low technology solution. That is, make speed agnostic, but then make crashes proportional to speed and other bad choices.

To that end, make any protective equipment illegal. Helmets, safety belts, airbags, ABS, crumple zones, red lights, and insurance aren't allowed. For drivers, a sharp spike directly pointed at the chests of vehicle occupants. For EUC riders, no protection whatsoever.

Would this slow people down? Would the survivors take undue care? Would people still be on cell phones knowing a mistake is likely to kill every one in the car?

[Darrell Wesh]

80kph please. The stopping distance is negligible. If you know what you’re doing, and opening up on long roads, you don’t ever need to stop on an EUC, just go around things that are moving slower than you. Someone emergency stops in front of you? No problem. Split lanes, pass on the oncoming lanes, etc.