Commentary: Why Are We Building Bikes Lanes That Are Hurting People?

Photos by Joshua Hart
Photo: Joshua Hart

As one of the certified bicycle safety instructors working with San Francisco’s Bike Ed program, the most important safety concept we try to get across to our students is that cyclists should never ride closer than 4 feet from any parked car. The reason is that getting ‘doored’ is the single most common cause of injury by motor vehicle users to people riding bikes in San Francisco.

People have been injured and even killed by riding in what is ostensibly a ‘safe’ space. Suddenly a door opens in front of them and they either have to swerve into motor traffic or hit the door itself.

Inevitably a student asks us, “But what about the bike lanes I see all over the city? A lot of them are totally within the ‘door zone.’ Where am I supposed to ride if the bike lane isn’t even safe?”

It’s a good question. Many of the city’s bike lanes have been built so that there is no clearance whatsoever between an open door and a passing cyclist. In the worst case scenario, a person with an older American car (Cadillacs have the longest doors) parks lazily, 2-3 feet from the curb. When they open their door, it can block the entire bike lane.

You might ask, isn’t it the responsibility of the driver to look over the shoulder before opening their door? And you would be right. CVC code 22517 requires that a vehicle occupant check for traffic before opening a door. Yet in the real world, people open their doors without checking all the time. And a person on a bicycle cannot reasonably be expected to look into every car to check whether there is someone inside. Under state law, cyclists have the right to ride where it is safe, which courts have affirmed is outside the dangerous door zone (CVC 21202).

Photo: Joshua Hart
Photo: Joshua Hart

So why are we designing bicycle facilities that are dangerous to use?  According to Caltrans chapter 1000 design manual [pdf], a bike lane adjacent to on-street parking must be at least 1.5m (just under 5 feet) wide. The minimum parking lane width is 7 feet (San Francisco Municipal Transportation Agency standards require 8 feet). Essentially that means if you are going to follow widely recommended safety practice and ride out of the door zone, but still in the bike lane, you have about one foot left to maneuver.

Photo: Bryan Goebel
Photo: Bryan Goebel

On San Francisco’s Fell St, the city’s designated east to west bicycle route, despite the new green paint, if you want to ride a bike safely, you are put in the unsafe position of staying within a one foot strip between the door zone and the motor traffic zooming by to the right.

Even if you are Kate Moss on a bicycle, you need more than one foot of width to safely maneuver. The American Association of State Highway and Transportation Officials (AASHTO) recommends that cyclists are given at least 4 feet of width (preferably 5 feet) to ride safely. Even if you are an expert at riding your bicycle in exactly a straight line, the likelihood is that you will veer into the door zone, or into the traffic lane at some point along your 3 block running of the gauntlet. If you follow official bicycle safety guidance, you should technically take the next lane over. But drivers see an empty bike lane and a “car lane” blocked by a cyclist in front of them and you have a perfect recipe for road rage.

So what is the solution? First off, bicycle design standards need to be changed to require cross hatch markings that extend 4 feet from a parked car so that even novice cyclists realize this a “no riding” area. If there is insufficient width on the street for a buffer and a bike lane, then a parking or travel lane needs to be removed. If providing for the safety and dignity of all road users is politically infeasible, then the bike lane itself needs to be removed and replaced with sharrows indicating that cyclists should take the travel lane.

It is no longer acceptable to lure people onto bicycles with a network of bicycle lanes that look inviting, but in reality can cause injury or death when used as directed. Our bicycle infrastructure design and our bicycle safety curricula should complement, not contradict, one other.


  • That was a great argument against something nobody was arguing.

  • @Aaron

    Well the I guess I’m equally as confused as to why you were pointing out the cost of motor vehicles and gas. Irrelevant to this conversation unless there was a subtle point your were trying to make?

  • So if everyone’s happy with the plan the SFBC has for reformation of the streets and addition of bike lanes/bridges, etc… What’s the point of this article?

    Is it just that the changes aren’t happening fast enough?

  • We were arguing for reducing car use, speeds, and space to relieve obstacles on other modes and benefit us all. You started defending public transportation access which nobody was arguing against. There is room on almost every street for plenty of bike, ped and public transportation access.

    I and others who were speaking also advocate transit-oriented development which prevents your situation you were describing.

    You also indeed were arguing against the cost of bike infrastructure. I brought up parking garages as a point of the expenses which bike infrastructure pales in comparison to.

    But I must point out: “Families with small children, elderly, handicapped, and many other groups are unable to use bikes as a viable transportation option.”

    Once again, go to cities like Copenhagen and you’ll see all of these groups on bikes and/or transit (just not handicapped on bikes).

  • Ask taomom, Dave. She posts regularly and will be more then happy to tell you how she manages on Muni and a bike (with limited car use, no one is saying the car needs to disappear, it just will “whether you like it or not”) with kids.

  • I am currently teaching my youngest son the basics of riding in a bicycle lane. Because he is only 5 this does not happen very much because in order for him to ride in a street I have to find either a very quiet street or have several people buffer him on a kinda quiet street. Dropping the fact that there are almost no places in the City for him to ride outside of GGP on Sunday when I finally got him out in the neighborhood on an unusually quiet day when I had my 2 older kids with me to buffer him he managed to endo because of a pothole right in the middle of the intersection.

    We have to do better than this. The only barrier to anyone in SF wanting to cycle from neighborhood to neighborhood should be not owning a bicycle.

  • Al

    One problem with Berkeley is that the ‘side-streets’, though certainly quieter and safer, are much less regular. I used to commute to Cal along College Ave, which is not the safest of streets, and so I just checked on Google Maps what the alternative would have been. The 4-step directions Google Maps gives for cars (which were essentially the way I used to ride) turn into a 14-step left right left left right left left right right… Trying to find your way around without detailed directions was always frustrating, where you’d think you were going the right way only to end up on a one-way road or going too far on a zig when you need to zag. As a result, when going a distance I stuck to the major roads. Even the safety benefit seems dubious when you consider all the turns and maneuvers you have to do.

    THAT SAID, I wouldn’t say no to some of those diagonal bollard lines in SF.

  • m

    “It’s not safer to have the bike lane on the right hand side of the cars, it is only slightly less dangerous”

    Huh? What is the difference between ‘safer’ and ‘less dangerous’? Are either perfectly safe? No. Nothing is. But I suspect the bike lanes on Fell are in exactly the right place, and even if a lane of cars was removed that particular lane would still be best on the left.

    Note my dooring incident above: it the last week I’ve been almost doored and almost right hooked in a place where I never had the problem before. Townsend, between 3rd and 2nd–the new bike lane means I no longer ride in the center of the right lane, but on the white line of the bike lane.

    I really like the idea someone proposed above of having the bike lane use the center ‘suicide lane’ instead of the outside–it’s weird because slow vehicles normally stay to the outside, but it works nicely for space reasons. I ride in that lane on Valencia somewhat frequently if conditions warrant.

  • m –

    Since Valencia’s traffic lights are timed for bike speed, 13 mph, cars can’t really travel faster than them anyway, so there’s no need for the bike lanes to be on the outside.

  • James

    I think I’m with peternatural on this one. I like bike lanes, even imperfect ones. The bike lane is my buffer against dooring. I ride along the left edge of it as well. A bike lane means I have ~5 ft of space where it’s rare that a car will ever pressure me to ride closer to parked cars. On roads that don’t have a bike lane, I definitely still stay out of the door zone, but if there’s any significant amount of traffic, it’s certainly less relaxed than having a bike lane. And I’m all for making my trips less stressful.

    I also like roads that are quiet enough not to need a bike lane, but for areas with heavy car traffic, bike lanes are great. It certainly doesn’t need to be vehicular cycling OR bike lanes. They’re complimentary, and it’s inevitable that someone who rides in bike lanes regularly will end up in regular traffic lanes regularly.

    I agree that one of the most important things to educate new cyclists about is keeping out of the door zone, bike lane or not.

  • m,

    Minneapolis just ripped out a center bike lane after over a decade of finding that cyclists didn’t like it.

    Among the problems with center bike lanes: how do you get to them? In Washington DC’s new center lane, riders frogger their way across the other travel lanes, ignoring the signs that tell them to use the crosswalk.

    Other problems include left turns by motorists, and my ongoing objection to making use of the road inflexible. You can have excellent rights to the road without having a piece of it sit empty when you’re not there.

    On dooring:

    I’ve never been doored, no close calls, after 52 years of riding, including many major American cities. My secret? I don’t ride in the door zone. Not one little bit. I stay out of both the door zone and the startle zone.

    I appreciate James’s thoughtful comments, but I also note that many victims of dooring accidents aren’t savvy people like James. They’re people who haven’t given this much thought, and they trust the bikelane designer too much. If 9/10 of the bike lane is unsafe, those people get nailed, and that is just wrong.


    On the cost of parking garages: I’d like to see every parking garage required to provide secure bike parking. They can charge for it, pro-rated on the space a bike takes compared with a car.

    I like shared infrastructure. A smooth, well-paved street serves everyone, is paid for by everyone, becomes a political whipping boy for no one. Sensible behavior is what makes this possible.


    My wife and I raised two kids. Her job is 15 miles away, over a mountain pass. When I last worked outside my home office, my job was 12 miles away, over that same mountain pass. We’ve both done it by bike, but that doesn’t work well for a daily routine. We have long found it necessary to be able to spring into action to make a lengthy car trip — to take a sick kid to the doctor 15 miles away, to deal with an ill parent 200 miles away, to work late, to go to a meeting 20 miles away.

    For these reasons, I think you raise a great point, which I will recast as follows: for many people in many communities, the distances and travel times are not bicycle-friendly. Let your rhetoric be sensitive to that and you’ll make more, not fewer, allies.

    John Schubert

  • Dave –

    Just cause I was thinking about this, I wanted to point something out in response to your earlier claim that road “maintenance is relatively cheap”. Putting aside your silly comparison of painting lanes to closing, de-paving and re-paving a road, building & maintaining roadways on average actually costs about $730 per year per vehicle. For San Francisco, with its 470,333 registered vehicles (PDF), that’s $343,343,090 per year (not unrealistic since the SFMTA’s budget is almost $800 million).

    On the other hand, let’s take the entire projected cost of the Connecting the City Plan, which includes three cross-city separated or traffic-calmed bike routes as well as “growing the current 55 miles of standard bike lanes to 128 miles of ‘next generation’ bikeways” at a total early estimate of $100 million. Keep in mind that bikes do virtually no damage to road surfaces and that this infrastructure replaces car trips with bike trips.

    Still think installing bike infrastructure is expensive?

  • “Families with small children, elderly, handicapped, and many other groups are unable to use bikes as a viable transportation option.”

    This claim is made so often (without any substantiation) that perhaps Streetsblog should post a FAQ debunking common myths about livable streets?

    Fact: Bicycles are a viable transportation option for families with small children! People all over the world use many forms of bicycles to transport children. Here in San Francisco, parents of young children use: bakfietsen, Xtracycles, trail-a-bikes, Burley carriers, tandem bikes, and bike seats of all kinds. I have personally ridden with my children in a bike seat from the age of six months on. I have also transported two 12 year olds at once on the back of my Xtracycle. (No mean feat.) Also note, in San Francisco it is legal for children up to age 12 to ride bikes on the sidewalk! This may not work on heavy traffic streets, but in calmer San Francisco neighborhoods I often see a kid riding on the sidewalk and a parent either on the sidewalk with them or riding in parallel on the street, with their child under their watchful eye. If you live up a hill, add an electric motor to your bike of choice. If I were to redo my early parenting years, I’d get a Bakfiets with a rain canopy from My Dutch Bike and take it to Len at Electric Bike Outlet and have him put on an electric motor. I could haul around three kids and groceries! So much fun! So little trouble! (I would also invest in a pair of sturdy disc brakes.)

    Fact: The elderly can ride bikes! They do in many places all over the world. And if a bicycle seems too unsteady, there are adult trikes and electrified adult trikes! The goal of the SFBC is to create bikeways safe and pleasant for folks from ages 8 to 80. Many elderly take public transit too! Yay for them! Actually, many elderly who get trapped at home right now when they can’t pass their driver’s test could be very well served by safe and extensive bicycle infrastructure.

    Fact: No one in the liveable streets movement would object to the handicapped using cars if that is the mode of transit that works best for them! In fact, with liveable streets, the traffic will be much less congested for the handicapped person to drive to wherever they are going. But for some handicapped, bicycling is much easier than walking, so good bicycle infrastructure would serve them well.

    Fact: “Many other groups” cannot be argued against if they are undefined! Indeed, it may be true that Martians and Venusians cannot ride bikes, and our desire to create bike lanes for the bulk of the human race is severely discriminatory. But for everyone else, bicycle transport (along with a good transit system) can be an excellent way to achieve and maintain health, happiness and prosperity.

    If the argument is that bicycles are not an alternative for people who have long commutes and no access to public transit, I would suggest that that situation is so untenable, it will disappear in the next ten years on its own. Those who have jobs will live within bike, ped or transit distance to work while the far-flung suburbs decay back into farmland.

    None of this means I never use my car. I just try to arrange my life so that I use it less and less each year. The nice part is that I always feel better, mentally and physically, after I ride my bike than after I drive my car.

  • Al

    I’ll grant that many people live and work 15+ miles apart, in places with bad weather, and where it’s otherwise impractical to bike. Fine. But that doesn’t describe San Francisco. Biking is practical for just about anyone who lives and works in the city– with some route planning, maybe an electric assist if necessary.

    Yes, there are people who commute in, and there are people who live here and commute out. But I don’t think the city should design its infrastructure around these people– make some accommodations, sure– because designing the city for people who live, shop and work nearby means that more people will do that, which means more business and a better quality of life.

  • Great essay and collection of photos of elderly and handicapped San Franciscans riding bicycles.

    (Am looking forward to future parts, Adrienne!)

  • Thanks for the nod, taomom! I was thinking of your comments when I wrote it : ) I would love it if you ever thought about writing some of your bicycling thoughts for us!!

  • Doug

    Re: safe Berkeley streets- hah.
    You mean like the left-side bike lane on Dana that ends with two lanes of motorists turning left in front of you onto Dwight and if you have safely crossed Dwight, you’re now in the wrong lane facing traffic?
    And if you ride safely and correctly taking the right lane, the motorist abuse and threaten you because there’s a bike lane on the other side of the street.

    And using the “bike route” when you’re crossing Ashby is a recipe for disaster, unless you dismount and walk across. There’s a light for pedestrians at Florence/Colby, but bicyclists aren’t entitled to the same protection at Hillegas.

  • Mick.V2


    The reference to Berkeley having a model that SF should copy wasn’t to suggest that Berkeley is a nirvana for bikes but rather to espouse an important principle.

    That is, that by segregating disparate traffic flows, cyclists will be safer. The idea in Berkeley, even if the execution is imperfect in places, is that you have large areas where traffic is calmed, through-traffic is disallowed and pedestrians and bikes can proceed without worrying about speeding traffic.

    While the speeding traffic is funneled into high-speed, high-volume arteries such as University, Shattuck etc.

    Cars get to where they are going fast, without being impeded by bike lanes. while bikes have priority in all other streets in an area of about one square mile.

    Cars aren’t going away, but they could be kept away from you.

  • patrick

    I like the traffic calming in Berkeley, but the idea that the arterials are fast in Berkeley is completely false. I lived there for twelve years, and I can assure you that with very few exceptions, the arterials are much slower than taking the alternative routes.

    Also, the traffic calming has very little to do with separating bikes from cars, and almost everything to do with keeping cars out of the areas where people live.

  • Doug

    My point was that separating cyclists onto “quiet” streets has real problems.

    I’d rather see more cyclists on the streets that are useful, since if there are more cyclists, automobiles will expect and respect them more.
    Share the road; integration, not segregation; separate but equal, isn’t.

  • Al

    I don’t think that it’s a problem to separate cyclists onto “quiet” streets. I think it would be great if there were a network of majority-cyclist streets, maybe even with only local car access (using bollards, speedbumps or such).

    The problem happens when the actual street choices are made– when the decision is made to make the cycling street the one with a 12-degree slope, because the alternative requires removing parking, or to leave a gap in the network because no one wants to figure out how to make it work and “they can take a detour: it’s only another mile”.

    Of course the worst is when a half-assed effort is made, and then is used as a justification to ban bikes from the best routes because “you have your bike routes, now use them”. If the routes are well-designed, bikers will naturally gravitate toward them, because they will simply be the best way to go.

  • Hi all,
    (1) Trip origins and destinations are on EVERY street. EVERY street has to be acceptable for cycling.
    (2) @ Al — on the subject of bollards and speed bumps: they cause many accidents to bicyclists, and I strongly suspect they also cause accidents to pedestrians as well. Two bicycle accidents I’ve worked on have involved bollards. In one, the injury was a shattered kneecap. The other — an impaled set of testicles.
    (3) Putting hazards in the roadway is a poor alternative to the REAL solution: that’s getting people to drive in a civil manner. Traffic engineers know perfectly well that people take their cues from the appearance of the street. When it’s broad and straight, they drive faster. So, having built a street for fast driving, they muck it up with speed bumps and injure cyclists in the process. (And don’t get me started on rumble strips.)
    (4) We CAN change the culture, but not by being a whiny special interest group. EVERYONE benefits from stepping back from mindless aggression and speeding on local roads and city streets. Don’t frame it as better for cyclists — frame it as better for everyone. Otherwise, cyclists are the 2 percent tail trying to wag the 98 percent dog.

  • Does data exist on the percentage of bicycle crash injuries in SF that are caused by dooring?

  • David, I don’t know if San Francisco has conducted such a study, and if they haven’t, I submit that they should not wait for such a study to begin anti-door zone riding measures.
    Here’s why: suppose you have a study that shows that dropping toasters into full bathtubs electrocutes children. Study was conducted in Peoria. Do you need to repeat that study to conclude that people shouldn’t drop toasters into bathtubs in San Francisco? No.
    That said, I believe there are studies showing huge percentages of crashes are dooring in Cambridge (may be a fifth of all bike crashes) and Toronto (two fifths). I apologize for not looking up the exact citation. But the information has been collected and it’s real. And somewhere on the Internet is a pretty long list of fatal dooring crashes worldwide, collected by John Brooking of Maine, and another collected by Riin Gill of Michigan.
    Riding in the door zone begets dooring accidents. The only sure fire way for a rider to avoid dooring accidents is to avoid the door zone — and not by an inch or two, because (a) you’ll misjudge the inch, and (b) you’ll still be in the startle zone, where you’re vulnerable to crashes caused by swerving. (If you hear people tell you to look inside parked cars for the driver…. ignore them. That has been useless advice ever since cars started having headrests, which was in 1968. Besides, you have other places to direct your attention. We wouldn’t ask motorists to look inside parked cars, because we want their eyes on the road. Same for cyclists.)

  • Just in case you want more of my anti-door-zone-riding rants, one I wrote is at the bottom of this page:

  • Mick-V2


    “I like the traffic calming in Berkeley, but the idea that the arterials are fast in Berkeley is completely false.”

    Yes, of course the word “fast” here is a relative one. The speed limit throughout Berkeley is 25mph and so, allowing for the usual margin there, cars can’t routinely travel faster than 30 mph without picking up a few tickets.

    But 30 mph is a decent speed for a small town – if you can maintain it, you could cross at least the flat part of Berkeley in a few minutes.

    So I am not arguing for 70mph in the city, outside of 13, 25 and 80. But rather the ability to maintain a reasonable but constant speed, by phasing the lights, deterring bikes, buses and people, and so on.

    It can be done and, indeed, is the principle behind freeways. So maybe 3 classes of road: freeway, arterial and calmed, with the latter being the vast majority of them.

  • patrick

    I didn’t say anything about 70? Personally I consider anything over 25mph too fast for any city street. It’s already been shown time and time that even 25mph can kill, and reducing the speed has distinct improvements on the number and severity of accidents, no matter the mode of transportation.

    You also seem to have missed the entire point of my post, which was that traveling on the arterials in Berkeley is slower than taking side streets, as long as you know the right ones to take.

    Why exactly do you think making things worse for bikes, buses, and people is a good idea? As I mentioned, higher speeds are clearly linked with more, and more severe injuries.

    Also, traffic calming has been requested by the residents of Berkeley, and they are still requesting more, all over the city. Most of these people drive, and they do it in Berkeley, so apparently they are more concerned with safety than saving a minute here and there.

  • If we’re going to base our arguments on circumstantial evidence, then it’s already been shown time and time again that anything over ZERO miles an hour can kill. That’s right, the more you move the more likely your risk of injury or death. So why are we willing to accept the speeds of bikes? It’s evident that there are far more pedestrians whose needs should be weighed in to the argument than cyclists. Anyone who regularly walks around a city has certainly had a run in with a cyclist speeding down the sidewalk. It’s frightening and causes accidents and injuries. If the bikes were removed from these areas, the city would be slowed down and the risk of injury minimized. Why should speeds be reduced to only accommodate cyclists?

    I say we go one step further. Within city limits, let’s ban any form of transportation that isn’t comprised solely of the human body. The acceptable forms include: walking, running, jogging, skipping, and the somersault or cartwheel for the occasional daredevil. Walking doesn’t require oil, it doesn’t require manufacturing in the way that bikes do, and if we ban shoes, there are no residual chemicals transferring to the streets, no waste products, and zero impact on the environment, unlike bikes. The streets would be extremely slow, and accidents and injuries would be virtually non-existent.

    We could go one step to further reduce the risk of injury by never leaving the house. If we work to increase virtualization of resources, the outdoor venture would become obsolete. By spending your entire life indoors, and away from others, you can completely remove all elements of obstruction or fear of incident.

    So who should we focus the restructure of the cities to accommodate? Many more people can walk than can bike. If we’re going to restructure the streets to remove or minimize cars because of their impact, I say we go one step further and remove all forms of assisted transportation. That way we can all walk around happy and enjoy a city with no issues.

  • Doug

    Dave, don’t be absurd.

    In fact, there are relatively few streets in Berkeley and Oakland where speeds of more than 25 (or even 20) MPH are entirely safe across the entire width of the street, given the lack of attention that many motorists demonstrate.
    We live with that.

    BTW, this: “You also seem to have missed the entire point of my post, which was that traveling on the arterials in Berkeley is slower than taking side streets, as long as you know the right ones to take.”
    leads directly to this:
    “Also, traffic calming has been requested by the residents of Berkeley, and they are still requesting more, all over the city.”

  • patrick

    Dave, cycling on the sidewalk is already illegal, and should remain so. I’m perfectly happy to ticket cyclists on sidewalks. I’m also perfectly fine with ticketing cyclists for speed violations.

    “Why should speeds be reduced to only accommodate cyclists?”

    Reducing automobile speeds is not to only accommodate cyclists, it’s actually a benefit to all road users. As I mentioned above, reducing speed lowers the frequency of injuries, so it is a benefit to drivers, cyclists, pedestrians, people in wheelchairs, etc.

  • EL

    @ Joshua Hart – Thanks for the link on the article. However, I couldn’t find any study or data in the article to support your statement:

    “getting ‘doored’ is the single most common cause of injury by motor vehicle users to people riding bikes in San Francisco.”

    Could you point me to someplace else that may have such data or info?

  • @EL
    That same stat was cited to me by the SFMTA and the SFBC when I did my post on dooring earlier this year.

    They list the stats on pg 14 of Chapter 5 in the Bike Plan and make the caveat that unsafe speed is listed higher than dooring, but there are concerns about police bias. If SFBC or SFMTA bike staff are reading this post, they could probably elaborate.

  • If 1998 to 2006 represents 8 years of data, with a total of 285 reported dooring incidents, that’s 36 per year.

    From the viewpoint of a cyclist injured seriously by a dooring those 36 incidents over 8 years are very important.

    On the other hand, if we have roughly 100,000 plus bike trips per day in San Francisco (I think that’s conservative), over 8 years that’s 292,000,000 bike trips! That makes your odds of getting doored low. I assume that cyclists that ride outside the door zone have an even lower chance of being doored. Is that a callous way of looking at it? I hope I’m not enraging the victims of dooring: not my intent.

    Maybe my math is wrong…

  • @Doug and @Patrick,

    I wasn’t just referring to the speed of cars, but to bikes as well. I’ll admit banning shoes is a bit absurd, but removing bikes from pedestrian areas is no less absurd than removing cars from bike areas. When I’m a pedestrian or runner, cars rarely drive on or near the sidewalk, so reducing motorist speed isn’t as important to me. In my times as a runner or a pedestrian, I have far more encounters and close calls with speeding cyclists than I do with speeding cars. If the speeding bikes weren’t there, I could walk and run in safety. Reducing cars to bike speeds might alleviate the potential for injury for bike riders but still poses a threat to pedestrians. It would stand to reason that in order to reduce and attempt to eliminate injury, we should slow all vehicles to the pace of the average pedestrian (about 3mph).

    Also, the jab at lack of attention by motorists gave me a chuckle. On average, I see at least as many people on bikes ignoring road rules and showing lack of attention to the safety of others as I do those in cars. The reason people in cars are more prominent is simply because there are more of them. I hope you’re not trying to assert that just because someone is on a bike they’re a model of safety and lawfulness. That, my friend, would be absurd. 🙂

  • @Dave, are you on mixed paths a lot?

    Also, a car going bike speed is going to still do FAR more damage then a bike going bike speed.

    And no one is saying cyclists are “a model of safety and lawfulness.” Come on now.

  • Anyone having frequent close calls should take a hard look at their own comportment. There’s a good chance they’re doing it wrong.

    As for safety (and courtesy) vs. lawfulness, they’re not the same. In my experience, most bicyclists in SF are reasonably safe and courteous, yielding when they’re supposed to (or when it’s just the nice thing to do). But they still roll through most stop signs (unlawful, but harmless).

  • Doug

    There were a couple of good replies already, but I will note that by their very nature, cyclists are MUCH more aware of their environment, even at their most inattentive, then almost all motorists. There’s no surrounding cage.
    Dave, you’re being absurd, still.

  • EL

    Thanks for the link Joshua. Even without the SPFD bias for unsafe speeding, looking at the total # of bicycle collisions, it’s about 50% the fault of the motorist and 50% the fault of the bicyclist.

    I think bicyclists are perceived to be outlaws because of the type of common bike violations (wrong way, failing to stop, failing to yield) versus the type of common motorist violations (dooring, failing to yield while turning, unsafe turning).

  • Back to the original topic, bike lanes. There is a design for bike lanes that sets off the door zone. You can view my diagram at I am not arguing for or against bike lanes (at least not here), and I will note that the total space outside the motor vehicle lane is 14 feet or more, so shared lane markings could also be a viable solution when this much space is available. I simply want to point out that there is a way of making bike lanes safe from dooring. Yes, wide SUVs will take up more than 7 feet of parking, but the buffer still works effectively. This diagram was reviewed by a number of bicycle educators, advocates, and engineers, and though that does not indicate agreement, it does indicate an idea worth considering.

  • patrick


    “I have far more encounters and close calls with speeding cyclists than I do with speeding cars. If the speeding bikes weren’t there, I could walk and run in safety.”

    “I see at least as many people on bikes ignoring road rules and showing lack of attention to the safety of others as I do those in cars.”

    Unless you provide supporting evidence, I will just assume you are making this up. I hear this claim often, but I’ve never seen somebody actually back it up with anything concrete.

    I’ll believe that drivers and cyclists violate the rules in about the same ratio or percentage, although it’s much more dangerous for a car driver to behave in an unsafe manner. If you are saying there are the same number of cyclists (or more) breaking the rules in an unsafe manner, then I’ll need to see some proof.

  • @Doug, this is the type of elitist assumption that makes arguments fall through the cracks. And in the same vain as patrick’s request, there is no evidence to support that bike riders are on average “more aware of their environment”. Doug, you are being prejudiced and making unfounded assertions.

    @patrick – What supporting evidence would you like? Should I walk around with a video camera strapped to me at all times? Should I stand at street corners for hours on end to video tape such occurrences? What type of evidence would show you that bike riders frequently ride on the sidewalks at speeds unsafe for pedestrians? You tell me what level of evidence would be acceptable for you and I’ll see what I can do to make it happen.

    Personally I see this effort as a complete waste of time simply because there’s nothing anyone here can do (or will do) to change the situation.

  • You could name streets at least. As I mentioned, I see cyclists on Embarcadero water front path, but that is a mix use path. I can’t recall a time I’ve seen a cyclist riding down SF sidewalks as if they were on the road, but that could be because I’m in the eastern, more dense, part of the city.

    Are you out on Ocean Beach? Are you on Masonic? Are you in GGP?

  • Dave:

    It’d be pretty hard for you to kill me on a bike. On the other hand, I could kill you with a car easily. The truth is, even if there was a higher chance of being crashed into by a bike than a car (which there is certainly not), you’d be a whole lot better off. Don’t get me wrong, I see bad cycling behavior, but I cringe mostly because they’re putting themselves at risks from cars more than anything, and just sometimes being rude to pedestrians (though rarely or hardly endangering). And that behavior is really a symptom of being in an unwelcoming, hostile environment, just as pedestrians are, due to bad design and danger from cars, which makes many feel like outlaws.

    What you’re doing here is ignoring the bull in the china shop.

  • patrick


    First, define the problem. So far all I’ve heard you talk about is sidewalk riding. If that is your issue, then, go and video for an hour or so and count the number of cyclists riding on the sidewalk vs. not on the sidewalk, then show how this is unsafe. If your concern is something else, then make a video oriented around that.

    Basically I’d like to see you use the scientific method.

    Or you could use research already performed by others and go and find some statistics related to injuries and fatalities caused by people riding their bike on the sidewalk (or riding anywhere else if you like), and then it would probably be useful to compare that to the number pedestrians and killed by cars.

    One source you could use if you go the research route is the Bureau of Transportation Statistics.

    (Here’s a hint: there are tens of thousands of times more people injured and killed by cars than by bicycles)

    Something makes me think you won’t actually go out and do this.

  • @Dan Allison – I think the minimum needs to be 15′ precisely becasue Trucks, Vans and SUVs are nearly 7 feet wide, thus making a 7.5′ parking stripe and buffer zone desireable. Here is a scale drawing in a publicly Available FaceBook album that shows what I mean:

  • @ Dan Gutierrez – Thanks for your comment and detailed drawing. Mine is the result of substantial discussions on the APBP list, but you aren’t a member there and didn’t have input. I basically modified it until I didn’t get any strenuous objections from the list, and at that point I let it be, knowing that it was too late to be included in the next revision of the AASHTO bike guide, but figuring it might be useful otherwise to bike facility planners. Thinking about it today, I agree with making the parking stripe at 7.5 feet because large vehicles are sadly common, but still feel OK with a minimum of 3 feet for the buffer. I realize that some doors are 3.5 feet, mine included, but felt OK about having 6 inches into the bike lane (as opposed to 3.5 feet, which is the norm for the unsafe design which started this discussion). I’ll give it some more thought, and maybe change my diagram and repost to the APBP list.

  • Hi all,

    (1) There is a steady trickle of bike/ped fatal collisions nationwide. There were two in Philadelphia within the last 12-14 months. Think of it this way: a bicyclist at 10 mph packs as hard a punch as Muhammed Ali’s fist. Aimed wrong, that punch will kill you. It can knock a vital organ, or topple the pedestrian so that her head smacks the pavement just so.

    (2) So what of combining bikes with pedestrians? It works reasonably well on trails where the pedestrians are all running or exercise walking. It works horribly on a sidewalk, where pedestrians do a half-dozen different activities, only one of which is going somewhere. Pedestrians mill about, dart from side to side unpredictably, and look one way while walking another way. This kind of pedestrian behavior generates many conflicts with cyclists. Yes, this has been formally measured in a study. I don’t have access to the study any more. I read it back in 1978.

    (3) Dan Allison, if a car door can intrude six inches into a bikelane, then a cyclist near the middle of the lane can have his/her handlebars just barely caught by the door. This can be instantly fatal. The handlebars are thrown to the right. The rider is thrown to the left, into the traffic lane, under the wheels of whatever passing vehicle happens to be there. That’s exactly how Dana Laird died. If a cyclist swerves to avoid an opening door, whether or not that door would have actually touched the cyclist, any collision subsequent to the swerving will be judged the cyclist’s fault. (Bob Mionske has written about that.) With all this in mind, I’m opposed to any traffic control device that puts the cyclist in either the door zone or the startle zone.

    (4) It’s an unusual city street that really has enough extra pavement width to accommodate an exclusive bike lane that is free of any dooring issues and also not uncomfortably close to overtaking motorists. (Yet another study, this one by Bill Hunter, has shown that you get less overtaking clearance with bike lanes than without them!) So when you don’t have all the width you could imagine, what’s the downside of the cyclist taking the right lane? The cyclist is free of dooring issues, he gets far more passing clearance from overtaking motor traffic, and he’s in a far better position to be seen by pedestrians crossing the street, by motorists at intersections and by anyone emerging from driveways. It’s win win win all the way around for the bicyclist’s safety and low-stress peace of mind.

  • grosser schwanz

    More idiotic proposal is hard to imagine. Ar all sidewalks so narrow or crowded, even can’t accommodate those few bikes?

  • smushmoth


    Since it is currently illegal for cyclists to ride on the sidewalk it is those who want to open up the sidewalks to bicycles job to prove that it is not dangerous using said scientific method. Most scientific studies have concluded that not only is it more dangerous for the legal users of the sidewalk, it is also more dangerous for a cyclist to be riding on the sidewalk then it is for them to be riding in the road.

  • Has anyone said that sidewalks should be opened bicycles? I think you are fighting a strawman smushmoth.


Reena with her road bike.

Another Crash on Valencia

Sunday evening, Reena (she asked Streetsblog to withhold her last name), 34, was returning to San Francisco after a long ride through Marin on her carbon fiber road bike. She turned onto Valencia for the last few blocks to her apartment in the Mission. She was pedaling along at a leisurely eight mph, riding in […]
A bike commuter high-fives an advocate for protecting him on the southbound Valencia bike lane during a May protest. Streetsblog/Rudick

Safety Vigilantes Strike Again on Valencia

Some 30 cycling advocates, wearing bright yellow t-shirts, stood along the southbound bike lane on Valencia Street between 16th and 17th streets and prevented Ubers, Lyfts and other cars from blocking this popular bike route during Friday evening’s rush. The protest, which emulated an earlier action on Golden Gate, was intended to ratchet up political pressure for […]

Should I Wear a Helmet Today?

The Naparstek boys riding last year’s Summer Streets event… wearing helmets. Sarah’s "Too Much Emphasis on Safety" post yesterday brings up the question in the headline above. A Canadian Broadcasting TV crew doing a documentary on biking is filming me as I take my two sons to school on our Dutch cargo bike today. While […]

San Francisco Gets Its First Green Bike Lanes on Market Street

The new green bike lane approaching Market and 10th Streets. Photos: Bryan Goebel. Cyclists who routinely ride on Market Street from Gough Street eastbound have no doubt noticed a steady stream of changes to the bicycle lanes as the San Francisco Municipal Transportation Agency (SFMTA) has been adding safe-hit posts and creating the impression of […]