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A comment on The Koch brothers are campaigning against tax rises for public transit projects. Parent comment

Re:The Koch brothers are campaigning against tax rises for p... by brianwawok on Tuesday June 19, 2018 @09:34AM (#17346395)
That picture doesn't make sense, because cars don't drive that close together, nor do bikes ride that close together.

Show 60 cars at 45 mph vs 60 bikers at 15 mph for a better density view.

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Re:The Koch brothers are campaigning against tax rises for p... by mcguire on Tuesday June 19, 2018 @09:50AM (#17346552)
"...nor do bikes ride that close together."

https://bicycledutch.files.wordpress.com/2013/03/amsterdam.j...

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Re:The Koch brothers are campaigning against tax rises for p... by brianwawok on Tuesday June 19, 2018 @04:24PM (#17350022)
I have ridden for years in the US, and you do not get that proximity of bikers outside of a peloton.
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Re:The Koch brothers are campaigning against tax rises for p... by bradlys on Wednesday June 20, 2018 @01:48PM (#17357730)
It's also not in the US. You don't see that number of commuting bikers anywhere in the US. That's not the point though.
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Re:The Koch brothers are campaigning against tax rises for p... by ufo on Tuesday June 19, 2018 @09:55AM (#17346603)
The minimum breaking distance between cars grows quadratically with speed. When roads are saturated they have higher thoughtput at lower speeds.
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Re:The Koch brothers are campaigning against tax rises for p... by a_imho on Tuesday June 19, 2018 @09:49AM (#17346539)
nor do bikes ride that close together

In my experiece they absolutely do, but it is rare to see a big pack together.

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Re:The Koch brothers are campaigning against tax rises for p... by throwaway76543 on Tuesday June 19, 2018 @09:49AM (#17346547)
You'll also want to take into account the 300% increase in speed. Transportation isn't about static density it's about throughput.

Objects moving 3x faster can be 1/3 as dense and have the same overall throughput.

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Re:The Koch brothers are campaigning against tax rises for p... by jcranmer on Tuesday June 19, 2018 @09:55AM (#17346610)
Higher speed actually translates into less throughput. Cars take up more than just their physical space; there is also a gap that is needed to stop safely in time--and this gap grows according to the square of velocity.

(You can argue that people don't usually leave sufficient space to stop, but I will point out that self-driving cars, which prompted this discussion, are going to be following those basic safety rules)

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Re:The Koch brothers are campaigning against tax rises for p... by throwaway76543 on Tuesday June 19, 2018 @10:20AM (#17346887)
No, higher speed always results in higher throughput given the same density.

Your complaint is that cars lower density as speed increases, which is true, but you're still looking at this too narrowly. Consider the bus.

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