David Zipper
@davidzipper.bsky.social
Senior Fellow @ MIT Mobility Initiative & Contributing Writer @ Vox, focused on transport, cities and tech. Words in Atlantic, CityLab, WaPo, etc. https://linktr.ee/davidzipper
Newsletter, speaking and advisory work: http://davidzipper.com
Newsletter, speaking and advisory work: http://davidzipper.com
Pinned
David Zipper
@davidzipper.bsky.social
· Jul 15
Look Both Ways Podcast: Episode 1
YouTube video by Look Both Ways with David & Wes
www.youtube.com
A bit of news:
@wesmars.bsky.social & I are launching Look Both Ways, a new podcast where we’ll debate everything transportation – from street design to robotaxis to fare-free transit.
First episode will be recorded live on Thurs, July 17th at 6p ET.
Join us then (and subscribe) ⤵️
🧵
@wesmars.bsky.social & I are launching Look Both Ways, a new podcast where we’ll debate everything transportation – from street design to robotaxis to fare-free transit.
First episode will be recorded live on Thurs, July 17th at 6p ET.
Join us then (and subscribe) ⤵️
🧵
$10.69 for a 15-minute ride?
For visitors, public bikeshare often feels like a ripoff.
In CityLab, I explored why.
For visitors, public bikeshare often feels like a ripoff.
In CityLab, I explored why.
Bikeshare Shouldn’t Kick Tourists to the Curb
Barcelona’s bikeshare program excludes non-Spanish visitors. Other cities charge tourists much higher fees to rent two-wheelers. Which policy makes more sense?
www.bloomberg.com
November 25, 2025 at 1:02 PM
$10.69 for a 15-minute ride?
For visitors, public bikeshare often feels like a ripoff.
In CityLab, I explored why.
For visitors, public bikeshare often feels like a ripoff.
In CityLab, I explored why.
In Oslo, four articulated buses trapped themselves in a roundabout yesterday.
"I don't know what I'm most impressed with: That they managed to get into the situation, or that they got out of it."
"I don't know what I'm most impressed with: That they managed to get into the situation, or that they got out of it."
– Vet ikke hva jeg er mest imponert over: At de klarte å komme seg inn i situasjonen, eller at de kom seg ut av den
Mandag kveld bød på komiske scener fra Alexander Kiellands plass.
www.ao.no
November 25, 2025 at 12:38 PM
In Oslo, four articulated buses trapped themselves in a roundabout yesterday.
"I don't know what I'm most impressed with: That they managed to get into the situation, or that they got out of it."
"I don't know what I'm most impressed with: That they managed to get into the situation, or that they got out of it."
This is really bad. Rad Power was already close to going under.
Rad Power owners should note that the company's newer batteries are not affected by the CPSC warning. Link in the story about how to check.
Rad Power owners should note that the company's newer batteries are not affected by the CPSC warning. Link in the story about how to check.
Rad Power Bikes' batteries receive major fire risk warning | TechCrunch
The U.S Consumer Product Safety Commission claims Rad Power "refused to agree to an acceptable recall." Rad Power says the CPSC's solution would bankrupt the company.
techcrunch.com
November 25, 2025 at 12:00 AM
This is really bad. Rad Power was already close to going under.
Rad Power owners should note that the company's newer batteries are not affected by the CPSC warning. Link in the story about how to check.
Rad Power owners should note that the company's newer batteries are not affected by the CPSC warning. Link in the story about how to check.
Induced demand: Same as it ever was
November 24, 2025 at 1:10 PM
Induced demand: Same as it ever was
The Finns are built different
November 22, 2025 at 5:39 PM
The Finns are built different
New research compares the use of electric and regular bikes in DC's Capital Bikeshare network.
Conclusion: E-bikes make bikeshare better.
"E-bikes enable broader dispersion across the city by connecting more distant bikeshare stations and supporting extended mobility."
doi.org/10.1016/j.tr...
Conclusion: E-bikes make bikeshare better.
"E-bikes enable broader dispersion across the city by connecting more distant bikeshare stations and supporting extended mobility."
doi.org/10.1016/j.tr...
November 22, 2025 at 5:29 PM
New research compares the use of electric and regular bikes in DC's Capital Bikeshare network.
Conclusion: E-bikes make bikeshare better.
"E-bikes enable broader dispersion across the city by connecting more distant bikeshare stations and supporting extended mobility."
doi.org/10.1016/j.tr...
Conclusion: E-bikes make bikeshare better.
"E-bikes enable broader dispersion across the city by connecting more distant bikeshare stations and supporting extended mobility."
doi.org/10.1016/j.tr...
In the latest @lookbothwayspod.bsky.social, I noted that economic arguments can broaden political support for limiting urban cars and creating bike-/ walk-friendly places.
It's working in conservative South France!
French urban planner: "Nobody wants to buy a coffee and sit in a parking lot."
It's working in conservative South France!
French urban planner: "Nobody wants to buy a coffee and sit in a parking lot."
November 21, 2025 at 4:28 PM
In the latest @lookbothwayspod.bsky.social, I noted that economic arguments can broaden political support for limiting urban cars and creating bike-/ walk-friendly places.
It's working in conservative South France!
French urban planner: "Nobody wants to buy a coffee and sit in a parking lot."
It's working in conservative South France!
French urban planner: "Nobody wants to buy a coffee and sit in a parking lot."
Reposted by David Zipper
New pod—our 10th!—is now up.
Much to discuss:
▪️ Could Trump really end federal transit funding?
▪️ Have Europe's urbanist reforms sparked a backlash?
▪️ Does anyone outside academia know what "transportation access" means?
and finally...
▪️ What's the best beer after a long bike ride?
Much to discuss:
▪️ Could Trump really end federal transit funding?
▪️ Have Europe's urbanist reforms sparked a backlash?
▪️ Does anyone outside academia know what "transportation access" means?
and finally...
▪️ What's the best beer after a long bike ride?
Episode 10: The Great Transit Defund, Access Means What??? & Europe's Backpedal
Podcast Episode · Look Both Ways with David & Wes · 11/21/2025 · 51m
podcasts.apple.com
November 21, 2025 at 1:19 PM
New pod—our 10th!—is now up.
Much to discuss:
▪️ Could Trump really end federal transit funding?
▪️ Have Europe's urbanist reforms sparked a backlash?
▪️ Does anyone outside academia know what "transportation access" means?
and finally...
▪️ What's the best beer after a long bike ride?
Much to discuss:
▪️ Could Trump really end federal transit funding?
▪️ Have Europe's urbanist reforms sparked a backlash?
▪️ Does anyone outside academia know what "transportation access" means?
and finally...
▪️ What's the best beer after a long bike ride?
Going live in 23 min! Link below.
Join us for Look Both Ways LIVE on YouTube at 5 PM EST
Look Both Ways LIVE with David & Wes: Episode 10
YouTube video by Look Both Ways with David & Wes
www.youtube.com
November 20, 2025 at 9:37 PM
Going live in 23 min! Link below.
In bike-friendly Copenhagen, the Social Democrats' candidate for mayor tried to win over drivers by calling for more car parking.
In elections this week, she was trounced. For the first time in 122 years, a Social Democrat won't lead Copenhagen. The new mayor is a socialist from the Green Left.
In elections this week, she was trounced. For the first time in 122 years, a Social Democrat won't lead Copenhagen. The new mayor is a socialist from the Green Left.
Danish Premier’s Party Loses Century-Long Hold on Copenhagen
Danish Prime Minister Mette Frederiksen’s Social Democrats suffered a major setback in local elections held across the country, losing the capital after more than a century in power.
www.bloomberg.com
November 20, 2025 at 2:27 PM
In bike-friendly Copenhagen, the Social Democrats' candidate for mayor tried to win over drivers by calling for more car parking.
In elections this week, she was trounced. For the first time in 122 years, a Social Democrat won't lead Copenhagen. The new mayor is a socialist from the Green Left.
In elections this week, she was trounced. For the first time in 122 years, a Social Democrat won't lead Copenhagen. The new mayor is a socialist from the Green Left.
Not mentioned in the story, but consistent with its findings:
Duffy has sat on USDOT's plan to address car bloat. A 2024 proposal would've required carmakers to adjust their front end designs to reduce the risk of deadly "head-hood" collisions.
Info: www.fastcompany.com/91195993/car...
Duffy has sat on USDOT's plan to address car bloat. A 2024 proposal would've required carmakers to adjust their front end designs to reduce the risk of deadly "head-hood" collisions.
Info: www.fastcompany.com/91195993/car...
NEW: Sean Duffy frequently calls safety his “top priority” as transportation secretary. But I spent months wading through regulatory notices and found something far different: that USDOT has been delaying, weakening and killing dozens of safety rules, many opposed by the transportation industry.🧵
November 20, 2025 at 2:03 PM
Not mentioned in the story, but consistent with its findings:
Duffy has sat on USDOT's plan to address car bloat. A 2024 proposal would've required carmakers to adjust their front end designs to reduce the risk of deadly "head-hood" collisions.
Info: www.fastcompany.com/91195993/car...
Duffy has sat on USDOT's plan to address car bloat. A 2024 proposal would've required carmakers to adjust their front end designs to reduce the risk of deadly "head-hood" collisions.
Info: www.fastcompany.com/91195993/car...
Good news: Congress is poised to prevent Trump from ending federal transit support.
"Asked whether he wanted to eliminate the mass transit account, [House Transportation Chair] Graves responded, 'No...it's been there for 40 years, and I want this to be a bipartisan bill...I'm just not interested."
"Asked whether he wanted to eliminate the mass transit account, [House Transportation Chair] Graves responded, 'No...it's been there for 40 years, and I want this to be a bipartisan bill...I'm just not interested."
November 20, 2025 at 1:53 PM
Good news: Congress is poised to prevent Trump from ending federal transit support.
"Asked whether he wanted to eliminate the mass transit account, [House Transportation Chair] Graves responded, 'No...it's been there for 40 years, and I want this to be a bipartisan bill...I'm just not interested."
"Asked whether he wanted to eliminate the mass transit account, [House Transportation Chair] Graves responded, 'No...it's been there for 40 years, and I want this to be a bipartisan bill...I'm just not interested."
New study finds that "vehicles with large driver-side blind zones are much more likely to strike crossing pedestrians while turning left."
Which vehicles have big driver-side blind zones? Those with thick A-pillars, bulky side mirrors, and tall hoods—i.e., big SUVs and trucks.
Which vehicles have big driver-side blind zones? Those with thick A-pillars, bulky side mirrors, and tall hoods—i.e., big SUVs and trucks.
Vehicles with big blind zones spell danger to pedestrians during left turns
A large driver-side blind zone raises the risk of striking a pedestrian during a left turn by 70%, a new IIHS study shows.
www.iihs.org
November 20, 2025 at 12:29 PM
New study finds that "vehicles with large driver-side blind zones are much more likely to strike crossing pedestrians while turning left."
Which vehicles have big driver-side blind zones? Those with thick A-pillars, bulky side mirrors, and tall hoods—i.e., big SUVs and trucks.
Which vehicles have big driver-side blind zones? Those with thick A-pillars, bulky side mirrors, and tall hoods—i.e., big SUVs and trucks.
Why is NYCDOT still funding this garbage?
Research is clear: These "please drive nicely" PSAs don't change driver behavior. They're a waste of taxpayer dollars.
Research is clear: These "please drive nicely" PSAs don't change driver behavior. They're a waste of taxpayer dollars.
November 19, 2025 at 11:17 PM
Why is NYCDOT still funding this garbage?
Research is clear: These "please drive nicely" PSAs don't change driver behavior. They're a waste of taxpayer dollars.
Research is clear: These "please drive nicely" PSAs don't change driver behavior. They're a waste of taxpayer dollars.
Almost half the Waymos on California streets are driving around empty. They're either waiting for the next customer or en route for a pickup.
If robotaxis scale, anything close to that level of deadheading would create crushing gridlock.
www.thedriverlessdigest.com/p/what-cpuc-...
If robotaxis scale, anything close to that level of deadheading would create crushing gridlock.
www.thedriverlessdigest.com/p/what-cpuc-...
November 19, 2025 at 7:14 PM
Almost half the Waymos on California streets are driving around empty. They're either waiting for the next customer or en route for a pickup.
If robotaxis scale, anything close to that level of deadheading would create crushing gridlock.
www.thedriverlessdigest.com/p/what-cpuc-...
If robotaxis scale, anything close to that level of deadheading would create crushing gridlock.
www.thedriverlessdigest.com/p/what-cpuc-...
The Trump admin's trademark street safety policy is very, very dumb
Lubbock Will Remove Buddy Holly-Themed Crosswalk After Federal Crackdown
www.nytimes.com
November 19, 2025 at 3:51 PM
The Trump admin's trademark street safety policy is very, very dumb
Microtransit is a threat to public transportation, not its savior.
Case in point: In Dallas, wealthy suburbs are using microtransit as an excuse to ditch DART, the regional transit system.
Case in point: In Dallas, wealthy suburbs are using microtransit as an excuse to ditch DART, the regional transit system.
What Will Replace DART if Cities End Their Contracts?
Two cities allowing voters to elect to leave DART in May have offered microtransit systems as an alternative. They're flawed.
www.dallasobserver.com
November 19, 2025 at 3:15 PM
Microtransit is a threat to public transportation, not its savior.
Case in point: In Dallas, wealthy suburbs are using microtransit as an excuse to ditch DART, the regional transit system.
Case in point: In Dallas, wealthy suburbs are using microtransit as an excuse to ditch DART, the regional transit system.
Smells like car bloat:
"More than 3,800 people were killed almost immediately when they were struck in 2023, an indication that high speeds and larger vehicles are making impacts more violent. The rate at which pedestrians are declared dead at the scene of the crash has more than doubled."
"More than 3,800 people were killed almost immediately when they were struck in 2023, an indication that high speeds and larger vehicles are making impacts more violent. The rate at which pedestrians are declared dead at the scene of the crash has more than doubled."
The deadliest roads in America
The number of pedestrians killed by vehicles has increased in the U.S., with road infrastructure and inadequate safety measures among key contributing factors.
www.washingtonpost.com
November 19, 2025 at 2:52 PM
Smells like car bloat:
"More than 3,800 people were killed almost immediately when they were struck in 2023, an indication that high speeds and larger vehicles are making impacts more violent. The rate at which pedestrians are declared dead at the scene of the crash has more than doubled."
"More than 3,800 people were killed almost immediately when they were struck in 2023, an indication that high speeds and larger vehicles are making impacts more violent. The rate at which pedestrians are declared dead at the scene of the crash has more than doubled."
When conservatives are in charge, how do you build support for limiting cars, expanding transit, and encouraging walking and biking?
The French Riviera offers lessons.
My latest, in Bloomberg
The French Riviera offers lessons.
My latest, in Bloomberg
On the French Riviera, Street Reforms Come From the Right
Politically conservative Côte d’Azur cities like Cannes and Nice have embraced pedestrianization, car bans and bike lanes. That’s a departure from global norms.
www.bloomberg.com
November 19, 2025 at 2:30 PM
When conservatives are in charge, how do you build support for limiting cars, expanding transit, and encouraging walking and biking?
The French Riviera offers lessons.
My latest, in Bloomberg
The French Riviera offers lessons.
My latest, in Bloomberg
All along the French Riviera, cities are limiting cars, building pedestrian zones, and boosting transit and bikes.
Most of their leaders come from the political right—not the left.
In Bloomberg, I explored lessons from the Riviera about building urbanist support when conservatives are in charge.
Most of their leaders come from the political right—not the left.
In Bloomberg, I explored lessons from the Riviera about building urbanist support when conservatives are in charge.
On the French Riviera, Street Reforms Come From the Right
Politically conservative Côte d’Azur cities like Cannes and Nice have embraced pedestrianization, car bans and bike lanes. That’s a departure from global norms.
www.bloomberg.com
November 19, 2025 at 1:30 PM
All along the French Riviera, cities are limiting cars, building pedestrian zones, and boosting transit and bikes.
Most of their leaders come from the political right—not the left.
In Bloomberg, I explored lessons from the Riviera about building urbanist support when conservatives are in charge.
Most of their leaders come from the political right—not the left.
In Bloomberg, I explored lessons from the Riviera about building urbanist support when conservatives are in charge.
Lyft's 2016 projection vs Lyft's 2025 reality
November 18, 2025 at 12:45 PM
Lyft's 2016 projection vs Lyft's 2025 reality
The mayoral candidate "'moved in' to a parking space in Copenhagen during her campaign."
www.theguardian.com/world/2025/n...
www.theguardian.com/world/2025/n...
November 18, 2025 at 12:27 PM
The mayoral candidate "'moved in' to a parking space in Copenhagen during her campaign."
www.theguardian.com/world/2025/n...
www.theguardian.com/world/2025/n...
China is bringing the hammer down on hyper-fast EVs, setting a minimum 5 seconds for accelerating from 0 to 100 KMH (62 MPH).
For context, the Rivian R1S hits 60 MPH in 2.6 seconds, as does the Tesla Cybertruck in "Beast Mode." (H/t @reillybrennan.com)
For context, the Rivian R1S hits 60 MPH in 2.6 seconds, as does the Tesla Cybertruck in "Beast Mode." (H/t @reillybrennan.com)
China mulls limiting cars' default performance as EV crashes frequently occur
China plans to require passenger vehicles to default to a state where acceleration from 0 to 100 km/h takes less than five seconds upon each startup.
cnevpost.com
November 17, 2025 at 12:10 PM
China is bringing the hammer down on hyper-fast EVs, setting a minimum 5 seconds for accelerating from 0 to 100 KMH (62 MPH).
For context, the Rivian R1S hits 60 MPH in 2.6 seconds, as does the Tesla Cybertruck in "Beast Mode." (H/t @reillybrennan.com)
For context, the Rivian R1S hits 60 MPH in 2.6 seconds, as does the Tesla Cybertruck in "Beast Mode." (H/t @reillybrennan.com)
Very disappointed none of you told me that Lewis Mumford made a 1963 film about car dependency, and it's available on YouTube.
"The motor car inflates our private ego, proclaims our social status, and provides us with the illusion of freedom and power."
www.youtube.com/watch?v=gIKZ...
"The motor car inflates our private ego, proclaims our social status, and provides us with the illusion of freedom and power."
www.youtube.com/watch?v=gIKZ...
November 16, 2025 at 8:51 PM
Very disappointed none of you told me that Lewis Mumford made a 1963 film about car dependency, and it's available on YouTube.
"The motor car inflates our private ego, proclaims our social status, and provides us with the illusion of freedom and power."
www.youtube.com/watch?v=gIKZ...
"The motor car inflates our private ego, proclaims our social status, and provides us with the illusion of freedom and power."
www.youtube.com/watch?v=gIKZ...
Reposted by David Zipper
Yet another evidence review argues very strongly that simply providing alternatives to driving doesn't reduce driving
This isn't surprising, if only thanks to habit. If I unthinkingly jump in my car for every trip (as many do), new buses won't change that
www.sciencedirect.com/science/arti...
This isn't surprising, if only thanks to habit. If I unthinkingly jump in my car for every trip (as many do), new buses won't change that
www.sciencedirect.com/science/arti...
Reducing traffic with “carrots”: A review of the evidence
Reducing traffic volumes is one way to reduce carbon emissions from the transport sector. Since increasing driving costs is often met with public resi…
www.sciencedirect.com
November 15, 2025 at 9:13 AM
Yet another evidence review argues very strongly that simply providing alternatives to driving doesn't reduce driving
This isn't surprising, if only thanks to habit. If I unthinkingly jump in my car for every trip (as many do), new buses won't change that
www.sciencedirect.com/science/arti...
This isn't surprising, if only thanks to habit. If I unthinkingly jump in my car for every trip (as many do), new buses won't change that
www.sciencedirect.com/science/arti...