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Re:Guerrilla Bike Lanes: San Francisco Makes Illicit Infrast... by nonethewiser on Wednesday November 04, 2026 @01:05PM (#50369268)
You misread me.

>Bikes don't belong on the road with cars and they dont belong on sidewalks with pedestrians and they don't belong in between.

The NYC bike lanes are inherently problematic. These are the "in between" that I'm talking about. They are not entirely separate paths in the way that I mean. They are a new lane within the existing path. What I mean by a separate path is something that is something above, below, or in an entirely different location than the road/sidewalk.

Normally, if you’re turning right you’re in the rightmost lane, so nobody to your right is going straight. And likewise for left. A bike lane puts straight-through traffic to the right of turning cars, coming up from behind in your blind spot. A “yield to bikes” rule doesn’t help much when you can’t see who you’re yielding to. And car traffic presents the same problem for bikes. They have to deal with this by merging all the way across traffic or cross and become a pedestrian. The fact that they may have to become a pedestrian is a major flag that they inherently dont fit.

Parking and buses have the same problem. The sidewalk and the road were designed to touch. Put a bike lane between them and every trip from the curb to a car or a bus has to cross it.

It’s essentially splitting 1 road into 2 with separate rules. It's inherently problematic. You can't introduce bikes without increasing the rule complexity and worsening the experience for everyone else.

There is plenty of basic intuition here.

- Pairs. Each pair of modes (car,bike,pedestrian) needs its own set of rules. Two modes is one pair. Three modes is three pairs, so adding one mode triples the relationships. - Introducing a "middle": Every segment of one street crosses every segment of the other. Adding a middle lane on both sides takes an intersection from 9 overlap zones to 25, and from 4 where different modes meet to 16. - Fixed width: The street doesn’t get wider. Every foot given to bikes comes out of car lanes, parking, or sidewalk.

Re:Guerrilla Bike Lanes: San Francisco Makes Illicit Infrast... by tough on Wednesday November 04, 2026 @01:09PM (#50369327)
the beltline on Atlanta comes to mind
Re:Guerrilla Bike Lanes: San Francisco Makes Illicit Infrast... by nonethewiser on Wednesday November 04, 2026 @01:36PM (#50369689)
I just looked it up and this is exactly what I mean by a separate location. Minneapolis has a bit of this too. I mean you could also use 3 dimensions space and put bikes up or down to resolve the core tension. All of these are of very limited viability so I understand from a pragmatic perspective why cities arent just doing this.
Re:Guerrilla Bike Lanes: San Francisco Makes Illicit Infrast... by tough on Wednesday November 04, 2026 @03:51PM (#50371333)
Yeah I think atlanta only got this as a freebie due to it being built on top of their abandoned rail road.

In europe there's also a great culture of bike /walking dirt only pathways too, but I agree its not very practical solution for cities

Re:Guerrilla Bike Lanes: San Francisco Makes Illicit Infrast... by jt2190 on Wednesday November 04, 2026 @01:15PM (#50369399)
> A bike lane puts straight-through traffic to the right of turning cars, coming up from behind in your blind spot.

Bike lanes making riders less safe has been known for decades. John Forrester’s book “Effective Cycling” [1] catalogues a lot of these dangers and warns cyclists to not assume that bike lanes are safer.

[1] https://mitpress.mit.edu/9780262516945/effective-cycling/

Re:Guerrilla Bike Lanes: San Francisco Makes Illicit Infrast... by hamdingers on Wednesday November 04, 2026 @01:22PM (#50369498)
John Forrester is globally recognized as a clown who's conclusions have never been supported by real world evidence. He worked for DOTs telling them what they wanted to hear ("don't build infrastructure for bikes") and in doing so set US infrastructure back decades.
Re:Guerrilla Bike Lanes: San Francisco Makes Illicit Infrast... by cyberax on Wednesday November 04, 2026 @02:07PM (#50370098)
So here's the thing. Seattle drank all the urbanistic Kool-Aid and started doing all the road sabotage with bike lanes, bulbouts, road diets, and so on with the goal to eliminate pedestrian and bike deaths.

What was the result?

A stunning INCREASE in pedestrian deaths and no significant effect on bike deaths: https://www.seattletimes.com/seattle-news/transportation/as-...

Re:Guerrilla Bike Lanes: San Francisco Makes Illicit Infrast... by hamdingers on Wednesday November 04, 2026 @02:48PM (#50370592)
Did they observe more crashes on roads that received upgrades? Doesn't sound like it, these are overall numbers. Maybe more people are walking/biking now, maybe just noise (10 and 18 ped deaths is really good for a major city already, in LA it's 160+).

Your personal theory is refuted by studies in the US, here's the classic lit review on this subject if you're interested: https://pmc.ncbi.nlm.nih.gov/articles/PMC2776010/

Re:Guerrilla Bike Lanes: San Francisco Makes Illicit Infrast... by cyberax on Wednesday November 04, 2026 @03:15PM (#50370885)
> Did they observe more crashes on roads that received upgrades?

No statistically significant correlation.

From my personal observations, sabotage of arterials resulted in a lot of traffic shifting onto the side streets that are much less safe. But our local DoT doesn't have enough traffic data to confirm or disprove this, I tried to FOIA it.

> Your personal theory is refuted by studies in the US, here's the classic lit review on this subject if you're interested: https://pmc.ncbi.nlm.nih.gov/articles/PMC2776010/

Look at the dates on these studies. Nearly all of them come from the period of the global crime drop, a result of the leaded gasoline phaseout.

I recently tried to replicate some of the studies of bike lane effects and quite often found the _opposite_ of the original studies. For example, in Seattle the business tax receipts declined more steeply on streets within 1 block of a protected bike lane compared to controls.

Re:Guerrilla Bike Lanes: San Francisco Makes Illicit Infrast... by hamdingers on Wednesday November 04, 2026 @03:34PM (#50371135)
I tried giving you the benefit of the doubt, but based on your word choices I can tell you're not approaching this topic in good faith.

Publish the results of your attempted study, then we'll talk.

Re:Guerrilla Bike Lanes: San Francisco Makes Illicit Infrast... by cyberax on Wednesday November 04, 2026 @04:17PM (#50371674)
Do an experiment: try to find papers in pro-urbanist publications that look past 2016 in the US cities like SF or Seattle. 2016 is a good starting point, as it's the year when a lot of Vision Zero construction kicked off.

Go on, I'll wait.

Still waiting.

Oh, there are almost no publications? Wonder why. And the ones that do appear tend to be relegated to rarely cited journals. E.g.: https://www.tandfonline.com/doi/full/10.1080/19427867.2022.2...

> We examined changes in counts and per capita rates of all, pedestrian, and bicyclist fatal motor vehicle collisions between 2007 and 2019 for 18 U.S. cities that took early Vision Zero pledges. Only 2 of the 18 cities have experienced statistically significant decreases in total fatalities since taking a Vision Zero pledge and only one city experienced a statistically significant decrease in pedestrian fatalities.

Re:Guerrilla Bike Lanes: San Francisco Makes Illicit Infrast... by jrowen on Thursday November 05, 2026 @01:19PM (#50382438)
So what exactly is your beef with urbanism? Would you prefer if we just focused on making car traffic as fast as possible and pushed aside other methods of transportation? Do you interpret these results as evidence that attempting otherwise is folly?
Re:Guerrilla Bike Lanes: San Francisco Makes Illicit Infrast... by cyberax on Thursday November 05, 2026 @03:11PM (#50383840)
> So what exactly is your beef with urbanism?

It's the root cause of all the current political problems in the US and Europe. It's a kind of pollution that offloads externalities (high living costs) from companies onto the population. Dense cities allow companies to more easily access larger pools of workers, without having to care about their long-term benefits.

> Would you prefer if we just focused on making car traffic as fast as possible and pushed aside other methods of transportation?

Yes. I would go as far as ripping out all the local transit (eventually). Self-driving cars have solved the only real problem with cars: people who can't or shouldn't drive (children, elderly, people with disabilities, etc.)

> Do you interpret these results as evidence that attempting otherwise is folly?

Yes. Quite simply: look at the stated goals of programs like Vision Zero. They are social engineering programs that simply use human lives as a way to push their agenda. I hate that.

Other urbanistic programs are similar, and even urbanists admit that: https://archive.strongtowns.org/journal/2023/4/26/upzoning-m...

> That sounds like a pretty big win to me?

Sure. But at what cost?

> Yes these programs are designed to make other modes of transport more attractive

No. They are designed to make car travel intolerable. It's a zero-sum game, a bike lane almost always means removing a traffic lane.

> What do you make of all the data that shows that adding lanes to a highway doesn't decrease traffic?

It's a real phenomenon - induced demand. And it also applies to housing costs: increases in housing density do NOT result in lower housing prices.

And the fix is actually the same in both cases: eliminate the _need_ for more lanes or denser housing.

Re:Guerrilla Bike Lanes: San Francisco Makes Illicit Infrast... by jrowen on Thursday November 05, 2026 @06:59PM (#50386327)
>Yes. I would go as far as ripping out all the local transit (eventually). Self-driving cars have solved the only real problem with cars: people who can't or shouldn't drive (children, elderly, people with disabilities, etc.)

One other problem with cars is that not everybody can afford one, or really should need to have one in a big city. Even if Waymo were a free or cheap public service, it's still far less efficient and more disruptive than a robust public transit system. When dense cities are walkable and bikable, less people need cars for everything. That's hard to achieve with cars at 40mph everywhere. There's a place for cars but we've only created the problem by having them zoom around every inch of a city at the expense of everything else.

Re:Guerrilla Bike Lanes: San Francisco Makes Illicit Infrast... by cyberax on Thursday November 05, 2026 @07:20PM (#50386506)
> One other problem with cars is that not everybody can afford one

That's incorrect. A typical bus/subway ride costs around $20, about the same amount as a car ride. We just heavily subsidize them, typical farebox recovery rate is around 15%, and that's not considering capital expenses.

Once shared self-driving cars become more common, we can just retarget the subsidies.

> Even if Waymo were a free or cheap public service, it's still far less efficient and more disruptive than a robust public transit system.

Self-driving cars with mild car sharing (2-4 people per car) will be more efficient than transit in almost all scenarios.

> When dense cities are walkable and bikable, less people need cars for everything.

Sigh. My point is that dense cities are now unliveable for the average person.

> or really should need to have one in a big city.

There shouldn't _be_ such cities. Giant metropolises are a failed experiment.

> Also, tax the companies, easy. In America we've been manipulated to loathe the ideas of taxes. Taxes are what pays for things that are good for everyone.

Yes. One good option is to tax the dense office space so that companies are incentivized to do remote work and/or offices in smaller cities.

Re:Guerrilla Bike Lanes: San Francisco Makes Illicit Infrast... by jrowen on Thursday November 05, 2026 @07:31PM (#50386598)
There shouldn't _be_ such cities. Giant metropolises are a failed experiment.

I see what you're getting at now, but they're as popular as ever (arguably more so) despite the legacy flaws. With what we know and the tech we have now, the cities of the future could wipe the floor with anything we have today, if we had the gumption to do it right.

Re:Guerrilla Bike Lanes: San Francisco Makes Illicit Infrast... by cyberax on Thursday November 05, 2026 @08:26PM (#50387006)
That's just how the human psychology works. If you can't avoid something, you'll justify that it's fine and you actually are enjoying it.

And the problem is that an average person _can_ _not_ avoid living in large cities. That's where all the good jobs are. My favorite example here is Tokyo: the housing market there is now completely unaffordable. In a country with _declining_ population.

This is not healthy. And this is _the_ reason for the recent unrest in the Western world. People are seeking easy answers: it's the fault of "corporations", migrants, NIMBYs, foreign investors, private equity, AirBnB hosts, etc.

> the cities of the future could wipe the floor with anything we have today

By not having any residents?

Imagine that you have an option to live in a single-family area with nice parks and plenty of personal space versus a closet-sized apartment on floor 11. What would you choose?

Re:Guerrilla Bike Lanes: San Francisco Makes Illicit Infrast... by jrowen on Thursday November 05, 2026 @10:25PM (#50387787)
That's just how the human psychology works. If you can't avoid something, you'll justify that it's fine and you actually are enjoying it.

White flight already happened though. Why are people moving back?

I believe the reason for the unrest is that technology and the attendant wealth consolidation have greatly outpaced our social systems and constructs. Life should be easier for people. We have the resources. We just don't have the collective will to make them work for the greater good. But yeah it's easier to point the finger at the bogeyman of the week.

You're referring to ideas I would consider to be in the tradition of the Garden City Movement. Certainly many people will always prefer the pace and the space of suburban life. But spend some time in the Eixample area of Barcelona if you get a chance. It doesn't have to be as crazy and inhumane as Manhattan or Tokyo. Some people figured out healthy city living 150 years ago and for some reason (cough, capitalism) the world largely ignored that information.

A reboot of those ideas with pre-planned modern infrastructure would crush. Move most high speed traffic underground. Make the ground level for people. Imagine an underground Waymo-Metro network that went in before the city above it.

Re:Guerrilla Bike Lanes: San Francisco Makes Illicit Infrast... by cyberax on Thursday November 05, 2026 @11:13PM (#50388095)
> White flight and urban decay already happened though. Why are people moving back?

Jobs.

"White flight" is also a US phenomenon, yet over-urbanization is happening everywhere. Look at Japan for an example. And it's a mono-national country without any significant internal racism or segregation.

Tokyo is also a nice counter-example for many proposals. It's building new housing as fast as possible (whole neighborhoods are construction zones!), it has a land value tax, it allows microapartments, it's building transit all the time. Yet nothing helps. Housing prices keep rising.

> I believe the reason for the unrest is that technology and the attendant wealth consolidation have greatly outpaced our social systems and constructs.

And over-urbanization is one of the reasons this became possible (not the only one, but definitely a contributor). An average company in a small town can't afford to treat people there like shit. They simply won't have any workforce or customers after a while. A company in a large city always has access to a pool of candidates.

> But spend some time in the Eixample area of Barcelona if you get a chance.

I grew up in Russia and Ukraine, and I also lived in Europe (Germany and the Netherlands). I got my driving license at 27 years and my first car at around 30 years of age.

And Spain has all the same problems as other countries: large cities are unaffordable, and small cities are dying. It's more relaxed in general, but the trend is unmistakable.

> Life should be easier for people.

Yes, and the only way to do that is to look at the root causes.

Re:Guerrilla Bike Lanes: San Francisco Makes Illicit Infrast... by jrowen on Friday November 06, 2026 @11:27PM (#50401610)
"White flight" was only a response to your assertion about human psychology. My point is that I think more people find urban life desirable and enjoyable than you give credit for. I don't care much for NYC, but it seems like every time I go to Europe there's those big ugly buildings on the wall. A restauranteur in Vienna once took us back to show us his memorabilia room with twin towers poster and all.

I think "make urban life better" has much higher potential than "convince people they don't want to live in big cities." I see the root causes as social and political more than technical. There are certainly advantages and efficiencies to be had with a dense population.

Unaffordablity due to wealth inequality and concentration is the major social dilemma of our time and I can't really connect it to people pushing for more bike lanes and park spaces.

Re:Guerrilla Bike Lanes: San Francisco Makes Illicit Infrast... by Manuel_D on Wednesday November 04, 2026 @03:18PM (#50370918)
Why would cycling infrastructure reduce pedestrian incidents? They'd presumably decrease cyclist collisions.
Re:Guerrilla Bike Lanes: San Francisco Makes Illicit Infrast... by cyberax on Wednesday November 04, 2026 @04:06PM (#50371522)
The infrastructure sabotage was done as a part of the Zero Vision program, that included both pedestrian and bike safety. It achieved neither.

> And since cycling has increased ~25% over the same time frame

The percentage of bike commutes in Seattle is in the noise, around 2-3% of the non-remote-work commutes. So the data is too noisy for any reasonable statistical significance.

For example, this year was deadly with 4 cyclist deaths (to date). In 2024 there were no cyclist deaths.

Re:Guerrilla Bike Lanes: San Francisco Makes Illicit Infrast... by jt2190 on Wednesday November 04, 2026 @05:57PM (#50372634)
[delayed]
Re:Guerrilla Bike Lanes: San Francisco Makes Illicit Infrast... by hamdingers on Wednesday November 04, 2026 @06:21PM (#50372827)
Modern on-street painted bike lanes were less than 10 years old in the US when Effective Cycling was published, only a handful of California cities had a few miles of them. The average US cyclist had never even seen one.

So the options at the time were riding on the sidewalk or in the street, and Effective Cycling became popular because it contained some genuinely good advice for cycling on a street with no infrastructure. Unfortunately Forester felt that this was the best and only way to safely cycle, which is why he immediately became popular with state and local DOTs who did not want to build bike lanes.

Re:Guerrilla Bike Lanes: San Francisco Makes Illicit Infrast... by jt2190 on Wednesday November 04, 2026 @09:57PM (#50374573)
I guess I don’t buy the narrative that we’d have some kind of cycling paradise in the U.S. if it weren’t for this one guy.
[dead]
Re:Guerrilla Bike Lanes: San Francisco Makes Illicit Infrast... by sellmesoap on Wednesday November 04, 2026 @11:13PM (#50375088)
I think the real issue is where is the space for the truly seperated bike lanes? I've personally experienced the new segregated lanes as a distinct regular threat to my safety as a cyclist, I was safer before the lanes were put in (at great tax payer cost and local businesses griping about less parking space) I'm in a smaller city now and they're spending a lot of money they don't have making these segregated lanes, creating the same problem all over again and making the driving feel claustrophobic to boot! I understand making a road feel less safe, or too narrow is a strategy to calm traffic down, but the old roads were just short of two lanes wide and felt quite safe in comparison. The worst spots in Vancouver aside from the dunsmiur upgrade I was referring to above are also bike corridors, a round about may slow a car down but for a 2 wheeler it does not, it's still not safe for the bike as cars try to cross or turn onto the bike lane, it truly is an all or nothing, I felt safer biking in raw Broadway or grandville street traffic then the adjacent mixed traffic bike corridors.
Re:Guerrilla Bike Lanes: San Francisco Makes Illicit Infrast... by jrowen on Thursday November 05, 2026 @01:06PM (#50382249)
Look up Robert Moses (NYC). Or Georges-Eugène Haussmann (Paris), or Ildefons Cerdá (Barcelona). These are general urban planners not strictly concerned with biking, but single individuals can have incredibly extensive effects on huge populations, that may last for centuries (for better or for worse).

In the US, not a single person, but the General Motors/Mack Truck/Firestone Tires/Standard Oil cabal exerted significant influence on shaping how our cities are built. Literally buying up streetcar companies across the nation to put them out of business, among other tactics.

Re:Guerrilla Bike Lanes: San Francisco Makes Illicit Infrast... by occz on Wednesday November 04, 2026 @03:50PM (#50371318)
John Forrester spewed completely disproven garbage and harmed cycling for decades by this influence on policy.
Re:Guerrilla Bike Lanes: San Francisco Makes Illicit Infrast... by cameronh90 on Wednesday November 04, 2026 @02:06PM (#50370086)
When you turn off a road, you need to look for pedestrians and motorbikes. Why is a bicycle so different?

For busy cycle routes, specific infrastructure to deal with this is installed like separate lights and banned turns to de-conflict the road.

Re:Guerrilla Bike Lanes: San Francisco Makes Illicit Infrast... by dgunay on Wednesday November 04, 2026 @02:53PM (#50370636)
Since bikes/scooters are much faster than pedestrians, it causes problems like this when they use pedestrian infra. For an example, I was driving up to a yield-to-peds xwalk a while ago, and on the sidewalk there was a scooter going at full clip. I slowed down because I had a hunch he would do this, but he took a hard 90 deg turn at the xwalk and went straight through at speed. If I hadn't done that, I might have run him over. A pedestrian could never have done that.

Something similar to this dynamic happens anywhere you would "look both ways" as a driver but don't have far enough visibility to extrapolate a safe window of passage relative to the speed of oncoming traffic. It can happen when parked cars block your view of oncoming traffic, or when parked cars block view of the bike lane, or when parked cars, trees, hedges, fences etc block view of the sidewalk that a non-pedestrian is using.

Re:Guerrilla Bike Lanes: San Francisco Makes Illicit Infrast... by asdff on Thursday November 05, 2026 @04:56AM (#50377291)
The issue is the parked cars not the bike lane. Planners are aware of this. There is recent efforts to “daylight” intersections as they call it when they work to increase these sightlines.
Re:Guerrilla Bike Lanes: San Francisco Makes Illicit Infrast... by hobo123 on Thursday November 05, 2026 @01:19PM (#50382430)
You say that, but routinely cars/trucks drive RIGHT NEXT to a bike lane with someone riding a bike, then pull right and drive over the cyclist like they couldn't have seen him or her.

Apparently the possibility of vision / line of sight is not the issue. Maybe the willingness, maybe the understanding that yes indeed, there is another lane next to the road, and maybe you should monitor it for traffic, especially before taking a right or left turn.

Re:Guerrilla Bike Lanes: San Francisco Makes Illicit Infrast... by clickety_clack on Wednesday November 04, 2026 @04:02PM (#50371474)
I think this reasoning is like “you can be right and dead”. If you’re cycling at 20km/hr, it’s very hard for a driver to see you whether you have the right of way or not.
Re:Guerrilla Bike Lanes: San Francisco Makes Illicit Infrast... by hobo123 on Thursday November 05, 2026 @01:20PM (#50382451)
Seeing someone ride right next to them doesn't prevent drivers from routinely killing cyclists while doing a right turn.
Re:Guerrilla Bike Lanes: San Francisco Makes Illicit Infrast... by kristjank on Thursday November 05, 2026 @04:40AM (#50377181)
Bicyclists are a lot faster than pedestrians while being even more fragile.
Re:Guerrilla Bike Lanes: San Francisco Makes Illicit Infrast... by sellmesoap on Wednesday November 04, 2026 @10:59PM (#50374998)
Yes I'd rather ride in traffic then be seperate, when I used to commute in Vancouver cars have a convoluted sign saying they are to yeald to bikes on right turn, or no right turn at all and I would get 'right hooked' at least once a week, I always had my eye out and would stop before getting pasted, but yelling at a driver who's in the wrong probably isn't helping them be aware of what they're doing wrong, I'm just 'yet another angry cyclist' since I'm upset they broke the rules and tried to kill me with their 4000lb+ metal brick!
Re:Guerrilla Bike Lanes: San Francisco Makes Illicit Infrast... by MattRix on Thursday November 05, 2026 @09:33AM (#50379563)
As self driving cars start to take over, this will become a non-issue, since they can drive more cautiously and don't have blind spots.
Re:Guerrilla Bike Lanes: San Francisco Makes Illicit Infrast... by hobo123 on Thursday November 05, 2026 @01:22PM (#50382475)
Meanwhile, can we please have laws that require trucks to have an electronic assistant checking if there's someone next to the vehicle when talking a turn?
Re:Guerrilla Bike Lanes: San Francisco Makes Illicit Infrast... by jrowen on Thursday November 05, 2026 @11:58AM (#50381472)
You can't introduce bikes without increasing the rule complexity and worsening the experience for everyone else.

Do you find two-way car traffic similarly inherently problematic? Left turns across oncoming traffic? I generally agree with you but it feels a little odd to rail against bikers in this way when car on car traffic is far more dangerous. But in car culture (which I am a card-carrying member of), we don't mind that!

Re:Guerrilla Bike Lanes: San Francisco Makes Illicit Infrast... by fakedang on Thursday November 05, 2026 @12:52PM (#50382090)
Put dedicated bike lanes on sidewalks. Easy. Which means making sidewalks wider. Not easy.