Improving Biking Is as Much About Slowing Cars as Building Better Bike Lanes

How stressful is this street to bike on? You can't tell from a photo. Image: Stewart Eastep.
How stressful is this street to bike on? You can't tell from a photo. Image: Stewart Eastep.

Since its founding 50 years ago, the top U.S. agency for investigating transportation injuries had been suprisingly quiet about a phenomenon that’s behind 30 percent of U.S. traffic fatalities.

Like much of the country’s transportation safety establishment, the National Transportation Safety Board had frequently avoided the subject of the speed of private cars. It did so even though the issue has been coming up since the very first collision the agency investigated, in Joliet, Illinois, in 1967.

Avoided the subject until this summer, that is.

In its groundbreaking report released in full last week, the federal agency laid the foundations for a major rethinking of transportation safety practices. The big idea in short, as Kathleen Ferrier puts it: “speed kills.”

“It’s the first time that we’ve seen national leadership on speed, and it’s coming from an authoritative voice,” said Ferrier, policy and communications manager for the Vision Zero Network, a campaign to eliminate fatalities and serious injuries. “The relationship between crashes and fatalities is complex, but the relationship between speed and crashes is very clear. Speed makes crashes more likely and the severity of injury more deadly.”

But many advocates of low-car transportation overlook the importance of traffic speed.

“I’ve been a bike/ped advocate for years and we’ve talked more about safe design than about speed,” Ferrier said.

One of the most important parts of bike infrastructure is invisible

Bike lanes like this one might be quite comfortable on a low-speed street. In this case, not so much.

Most of the NTSB report combines recent data and long-term trends to show how many fatal collisions are caused by excessive auto speed. Speed-related death, for example, is “comparable to that attributed to alcohol-impaired driving.”

And yet it’s sometimes implied that auto speed is unchangeable behavior — for example, in parts of a separate bike safety report published Thursday by the Governor’s Highway Safety Association. That report dedicates an entire section to alcohol as a factor in bike-related fatalities but doesn’t even mention auto speed in that context. (To its credit, the GHSA report goes on to discuss and recommend many policies to reduce auto speeds anyway.)

Even biking advocates can be guilty of overlooking speed as a factor in bike infrastructure. Slower-moving cars don’t photograph as nicely as a green-painted protected bike lane, but they’re just as important to whether most people feel comfortable biking on a road — even when a new bike lane isn’t in the works.

“In my experience, speed is seldom discussed until a new bike or pedestrian facility is proposed,” said Jennifer Ruley, a senior project manager for the New Orleans transportation department who works on bicycle projects, reflecting on conversations among people who care about bicycling. “That’s just crazy.”

In the new PlacesForBikes Bike Network Analysis of various U.S. cities, we always look at two factors when calculating the “stress level” of biking on a given street: the roadway design (auto lane count, bike lane width, separation type, and the presence of parking) and the posted speed limit.

That’s based on work by Northeastern University’s Peter Furth, who concluded that auto speeds interact with bikeway design to greatly affect people’s willingness to bike on a street.

What cities, states, and advocates could do to help

Neighborhood bikeways make biking comfortable on side streets simply by slowing and reducing auto traffic.

What can biking believers inside and outside of government do to reduce dangerously fast driving?

One way might be to pay at least as much attention to too-wide auto lanes, which increase people’s “natural” driving speed, as to too-narrow bike lanes.

Another might be to support four-lanes-to-three road redesigns even when the changes don’t include bike lanes, because those designs prevent bad drivers from weaving between lanes in order to get to the next red light more quickly.

On heavily signalized streets, cities could create green waves that give continuous green lights at 20 mph or 12 mph, making it pointless to drive at a lethal speed.

And as the NTSB report recommends, states could give cities the right to use safety cameras — already in wide use on the dramatically safer streets of Europe — to automatically issue fines to scofflaws who ignore speeding laws.

The NTSB report also questions the longstanding “rule of thumb” that speed limits should be set based on the natural speed at which 85 percent of people drive. The NTSB recommends also considering other factors, including recent collision and fatality rates, when setting speed limits.

“They’re basically saying it’s time to reevaluate these outdated practices that have been rules of thumb since the 1950s,” said Ferrier. “But they haven’t been reevaluated, and they’re leading to death on our streets.”

PlacesForBikes is a PeopleForBikes program to help U.S. communities build better biking, faster. You can follow them on LinkedIn, Twitter or Facebook or sign up for their weekly news digest about building all-ages biking networks.

91 thoughts on Improving Biking Is as Much About Slowing Cars as Building Better Bike Lanes

  1. You’re not helping Western Girl with her ignorance, Stuart, by sharing your own. CEQA, the most important environmental law in Caifornia, was passed in 1970, when Ronald Reagan was governor:

    The point of our successful litigation was compel our city government to do an environmental study of the ambitious, 500-page Bicycle Plan before it began implementing it on the streets of the city, which is what the law clearly required. CEQA doesn’t in fact “prevent” projects from being implemented. It just requires environmental review before they are.

    It was an easy decision for the judge to make:

    That plan proposed taking away thousands of street parking spaces and dozens of traffic lanes on busy city streets to make bike lanes, an obvious environmental impact, since reducing already scarce street parking in SF and eliminating traffic lanes on busy city streets could lead to increased traffic congestion and thus more air pollution.

  2. Oh, Western Girl, I didn’t mean to make you sad! I’m not angry or an “auto advocate.” I haven’t owned a car in more than 20 years and walk and take the bus in SF. But the reality is that most people rely on motor vehicles to get around, and cycling, even in SF, is still only practiced by a very small minority in spite of years of pro-bike, anti-car propaganda from City Hall and the Bicycle Coalition.

    Deliberately making traffic worse by taking away traffic lanes as in Playa Del Rey is not helpful to the bike cause. On the contrary, it just makes you seem like elitist jerks.

    But City Hall is also doing that here in SF:

  3. ” Safety equals 85th percentile speed limits, longer yellow lights, and stop signs only where needed.”

    As always, you forgot to add what you really meant: “safety for car users” and “stop signs only where needed for car users”.

    “OK, so we make narrower lanes and fewer lanes, then have more crashes, and congestion.”

    Only if (1) the amount of cars people drive stays the same, and (2), people don’t adjust to the new realities.

    “All the eco-people out there had better realize that as you create congestion, you waste energy and pollution increases.”

    Again, you’re working on the assumption that (1), the number of cars on the road is a fixed quantity, and (2) that gasoline powered cars are going to keep their current hold on the market. Those two assumptions are not automatically true in every place.

    “More research needed before the next article is written.”

    Are you talking about actual research or just reading NMA press releases?

  4. You are incapable of having a rational discussion, so I will not waste my time. I learned that in the past.

  5. And that’s relevant to me showing that your own source shows that your claim that “Cycling is the cause of most head injuries treated in emergency rooms” is a complete fabrication how, exactly?

  6. I wouldn’t ride a bike, because it’s too dangerous.

    Some people view the fact that biking is more dangerous in the US than in a number of other countries as a problem to be addressed by building better bike infrastructure.

    Others actively obstruct efforts to build better bike infrastructure.

  7. The ‘full disclosure’ Rob failed to mention: It is his own blog. Read the comments. He’s been making these claims and been soundly refuted since 2009 (at least).

  8. ???? now you jump to helmets? Oh dear Rob, RichLL, ect. Again, it would be great to have an honest conversation. However, your comments sections takeovers on here where you successfully take any value out of the conversation is just sad. Blocked again. Get busy on your next profile to get your next response from me.

  9. When a person is killed or seriously injured while riding a bicycle, why does it matter who’s fault it was? Everyone makes mistakes because we’re all human.

    When our streets are designed in such a way that any split second error in judgement results in blood being spilled and lives destroyed, who is guilty of making that mistake isn’t relevant. The goal of safer street designs is to allow greater safety margins which will result in fewer collisions and will cost less than the staggering high cost we’re currently paying for all the blood that pours down our poorly designed streets.

  10. I don’t ride a bike, either, and I have no interest in riding a bike, but I don’t see the need to obstruct efforts to make biking safer, since I’m not a selfish jerk.

    Besides, the bike lane installations where I live have also made the streets safer for pedestrians and motorists.

  11. Not on city streets, as you’e been told many times. The 85th percentile approach comes out of a 1964 paper about rural roads. Aside from being over half a century old, it never had any bearing on city streets.

  12. 1) Your post (like Frank says) is based on anecdotal evidence rather than comprehensive data.
    2) The numbers you do cite don’t specify whether they differentiate between road biking and mountain biking.
    3) Like a comment on your post says, you gloss over the difference between injuries and fatalities.

    Let’s see if you follow through and improve yourself, or whether you continue as you’ve been doing and try to propagandize against bicycle access.

  13. I’m with you, Andrew. I don’t ride a bike very often, but I’ve noticed that where bike lanes (especially protected bike lanes) and other road-diet features have been installed, that the street generally feels safer and more comfortable to walk along (and across).

  14. Why would you want to risk your life while going about on your daily errands? In more than 70 years as a passenger in cars, trucks, and buses, I’ve never been in an accident, let alone a life-threatening accident. Riding a bike has intrinsic risks that can’t be prevented by street design. Don’t do it.

  15. No, those writers understand that mountain biking is a special case and different than road biking. For one thing, mountain bikers are more honest about their speed/thrill motivation for than cyclists are in San Francisco, those I see speeding down the hills in my neighborhood and running stop signs.

    Why take the chance of either injury or death by riding a bike?

  16. You never read the formal paperwork for it, or the federal report which discussed speed limit setting and how it affects behavior. The people pushing bad laws have selective amnesia with stuff like this.

  17. The risks of sitting in a car are far worse in the long run for human health than the risks of riding a bicycle. I used to weight over 220 pounds and ride Muni to work each day. As careful as I am crossing the street, I had near misses with inattentive drivers about once every 3-4 weeks just walking the 8 blocks over to Van Ness from my home. Since I’ve bought my first bicycle 4 years ago, I’ve lost 50 pounds, and riding my bicycle in city traffic I experience near misses only about once every 6 months. Collision statistics by the SFGH trauma center confirm this; walking in SF is more dangerous than riding a bicycle. I’m very risk averse so I tend to ride and walk very carefully.

    I used to believe in the myth that riding a bicycle in the city is inherently dangerous. In my case, not riding a bicycle was a much greater risk to my life than riding one. Since I started biking, I’m happier and healthier than I’ve ever been in my life. More importantly, I never need to ride Muni or sit in congested city traffic ever again!

  18. Do you feel the same way when you get into a car and go 70 mph on the highway, putting your life in the hands of all those strangers driving around you? Probably don’t even think about it.

    It’s true that there are a lot of ways to crash a bicycle, but I wish you would stop dropping my name to scare people away from bicycling. It’s not for everybody, but bicycling would be a great, reasonably safe option for tens of millions of Americans who currently drive everywhere.

  19. San Francisco is the most dangerous city in the west for pedestrians, due to cars. Cars hospitalize 2-3 people a day in this city, and kill someone every 3 weeks. (The last fatality was 2 days ago, ending the life of one of the best people I’ve ever met.)

    While I am appropriately outraged about cars injuring and killing bicyclists in this city, with complete impunity, I am mindful that this mode of transportation is much safer than walking and motoring in this city. One of the blog entries Rob keeps flogging is his take on a hospital tally of bike injuries that he says proves that bicycling is so dangerous, but there’s no sense of proportion or any sort of common denominator in that take.

  20. In his neverending quest to avoid statistics based on a common denominator, Rob also fails to consider the head injuries caused by the lack of motoring helmets.

  21. What numbers are you looking at that show cycling being safer than driving in SF? For fatalities, the ballpark figures from Vision Zero reports are about 10x as many cyclist as motorist, and the SFMTA mode share numbers for trips put driving at about 10x cycling, which makes it roughly 100x as dangerous for fatalities.

    I haven’t seen injury data, but I’d be surprised if it weren’t skewed the same way; an armored shell is handy if you’re the one inside it instead of hit by it.

    Cycling vs. waking is harder to compare since trips are unlikely to be comparable lengths on average. Ideally you’d want miles travelled as the denominator for all of this.

    Cycling isn’t sky-is-falling dangerous like Rob wants to convince people by lying about data, but the numbers I have seen certainly don’t suggest it’s the safest (for the person doing it) option.

  22. Perhaps that is because both cars and trucks take much longer to stop from the same speed as bicycles do, AND the fact that bikes aren’t required to have working brake lights as all other vehicles on our roads are, which could save as much as 1-2 seconds of driver reaction time.

    Did you bike advocates know that a loaded 18-wheel truck or a loaded city bus can take 3 times the distance to stop from 30 mph as a car can stop within?

  23. I can tell you about my own history of bike riding from 1961 to 1975, when I wiped-out on my bike more than a dozen times, several times at fairly high speed, and never got hit by a car or by another other powered vehicle either.

    I did get hit in the head by a rock thrown at me by some other kids once which caused a big wipeout, and a couple of times I hit some sand and gravel that had washed across the road from a hard rain in a downhill curve and crashed at high speed too.

    One time I had the rear wheel bearing on my single-speed Schwinn explode and freeze up my rear wheel when I was going down a steep hill at high speed causing another bad crash. Another time I crashed trying to pull into a gravel driveway off a paved street, and one time I crashed really hard on my bike after hitting the big jump wrong when I was 12 too.

    Nope, even though I grew-up in suburban Detroit before the era of bicycle lanes and regularly rode on 2-lane roads with 45-50 mph speed limits and gravel shoulders, I never got hit by a car.

    As a professional driver I have driven over 4 million miles since 1972, more than 3 million miles in an 18-wheel truck, and I never have had an accident where anyone was hurt or killed, though I will admit that I have been lucky a few times too.

  24. Perhaps, Mark, Perhaps….I’ve been hit from behind twice on my bicycle. Both times in broad daylight. The second time, the car behind the car that hit me saw the whole thing and said the car swerved possibly on purpose to hit me. No I didn’t do anything to them. So Perhaps it is not that the motorist doesn’t see the bicyclist (for lack of tail lights) but rather that they : 1. don’t want to see the cyclist, 2. are not paying attention 3. even think it is funny to run the cyclist off the road. Or who knows, but you have no evidence for your brake light statement and other information I’ve seen seems to indicate that tail lights are only moderately successful at providing visibility. To address your other issue, I’ve taken physics but thank you for mansplaining and assuming that bicyclists somehow wouldn’t know physics. Indeed the cyclist who was tragically killed near where I live was a physics professor. I won’t go into details. i do wonder, when driving, whether other motorists who pull directly in front of large trucks are aware of the physics of that situation. Also I read a few of your other responses and you are funny and well read. But Perhaps not perfect. Close though.

  25. Now my next question is, if cycling is responsible for “19% of a subset of head injuries”, and as a percentage of total car trips cycling is less than 2%, and considerably less than 2% of total vehicle mileage, would it be fair to just multiply cycling head injuries by 50 to estimate what total head injuries would be if all movement now done by cars was done by bicycle instead?

    Or, should the figure be higher considering that a higher than normal percentage of car accidents occur at night and during weather conditions not-conducive to cycle riding? After-all, how many cycle riders have ever fallen asleep while riding before?

  26. Perhaps the main reason that the number of bikes getting hit from behind is so high is that #1: Bikes don’t have brake lights, which greatly increases following driver reaction time when bike riders suddenly slow, and that #2: The human brain has a much more difficult time judging a reduction in speed of smaller moving objects ahead rather than that of larger moving objects ahead when neither have working brake lights.

    After doing some research myself and posing the question of the increased reaction time involved in recognizing slowing ahead without brake lights to a PHD transportation professional we came up with some helpful peer-reviewed science that I feel bike riders should be aware of.

    According to Triggs & Harris (1982), their finding on driver
    recognition and reaction time to brake lights ahead was 1.26 seconds with a standard deviation of .28 seconds, but driver recognition of and reaction to other stimuli was as high as 3.6 seconds with a standard deviation of .77 seconds.

    Frankly that is a 2.34-second difference, which at 30 mph or 44 feet per-second is a 103 foot difference.

    Marc Green, PHD published a commentary entitled “Driver Reaction Time: Nature of the Signal” on his transportation engineering blog. His findings on multiple different aspects of drivers recognizing road hazards ahead found that drivers are much quicker to recognize conflict approaching from the side than decelerating conflict ahead.

    He also produced two other studies that are helpful to this topic.
    According to Marc Green [Quote] “Summala et al” found 1-2 second slower following driver braking reaction without brake lights, but the actually time difference depends on the situation.

    Reaction time to deceleration, actually looming, follows Pieron’s power function Law (Molinar, 2005), so RT is faster as deceleration rate is greater.

    Also, perceiving deceleration of small objects is much more difficult since angular expansion is (width*speed)/distance. It is much harder to detect slowing in bicycles than in cars because they are much narrower.

    Really, bicycles need brake lights even more than cars because their speed changes are very hard to perceive. [End quote]

    Molinar, J. L. (2005), Response time asymmetries
    between expansion and contraction. Psicológica: Revista de Metodología y Psicología, Experimental, 26, 139-145.

    Summala, H., Lamble, D., & Laakso, M. (1998). Driving experience and perception of the lead car’s braking when looking at in-car targets. Accident Analysis and Prevention, 30, 401–407.

    Triggs & Harris (1982), Reaction Time of Drivers to Road Stimuli, Monash University, pages 42-44

    Also, the issue of differential in large vehicle stopping distance versus small vehicles has been studied by the Department of Transportation of every State in the US and by the Federal DOT.

    The median difference in stopping a large air-brake equipped vehicle versus a smaller hydraulic brake-equipped vehicle is aggravated by air-brake application time, which is about 1/2 second in tractor-trailers and slightly less in city buses.

    In total the average loaded 18-wheel truck takes 2.5 times the total distance to stop from any speed as does the average car, while loaded city buses and both 6 and 10-wheel trucks average about double the stopping distance as the average car from the same speed. Bicycles can stop from that same speed in even less distance than a car. How is that safe, especially when bicycles don’t have brake lights?

    From 55 mph the difference between average auto stopping distance and average loaded 18-wheel stopping distance is over 400 feet. Street trolleys running steel wheels on steel rails have an even greater stopping distance than do heavy trucks or buses from the same speed too.

    In a prior urban planning discussion on this same subject 2
    years ago with some bike advocates an electrical engineer there figured that an LED bike brake light system powered by a 9-volt battery that could work off of either deceleration or brake cable travel would only add about 1 lb. to bicycle weight.

    In my professional opinion the savings in following driver reaction time made possible by adding brake lights to bicycles operated on roads would greatly reduce the incidence of bikes getting hit from the rear.

    However, bike riders must realize that no driver can give 100% of their attention to the bicyclist ahead, as drivers are constantly scanning their speedometer, other dash instrumentation, their rear-view mirror, and also watching for conflict approaching from the side, while trying to dodge potholes too. There are plenty more driver distractions that subtract from time spent looking forward at the road too.

    Also in my professional opinion, bicyclists wanting to avoid accidents should stay off of roads with heavy truck traffic and city bus traffic due to the stopping distance differential issue, as well as off of streets with trolley tracks inlaid in the pavement, both due to the stopping distance differential, and because bike tires and inlaid trolley tracks have their own safety problem, that has caused lots of bike riders to lose control and crash too.

    Perhaps fat tire bikes might have less of a problem with inlaid trolley tracks than narrow tire bikes, though even motorcycles can have issues with inlaid trolley tracks.

  27. This is excruciating research. But IT is built upon fundamental assumptions not covered by the published information. There is no evidence that bicyclists are hit from behind because they are slowing or stopping. A simpler explanation is that CAR drivers dont see bicyclists. It isn’t normal for bicycles to travel towards cars. Car drivers hit things and people all the time. Bicycles are just another casualty of cars. In my experience , and reverting to the topic of this article, people drive too fast. I have experience riding on streets with buses and prefer that because the drivers are professional.

  28. We share some crash history, most of my bicycle crashes were my own damn fault as Jimmy Buffet put it, and didn’t involve a motor vehicle, but I’ve also been hit by two motor vehicles while riding legally and visibly in day light, had one roll over my foot while riding on a sidewalk (not legal or advisable, but “felt” safer at age 12) and ran into two stopped cars as well. I was definitely injured when I rolled a golf cart over myself.
    While not a professional driver, I pride myself on defensive driving since my foolish teenage years, yet I’ve been in several injurious car crashes with some near misses that could easily have been fatal, as driver or passenger. Almost all were other driver’s errors, sometimes speed related, always due to aggression, distraction or impairment.
    I agree that two wheeled cycles are inherently unstable, which is why my new improved SafetyCycle! concept is an enclosed tadpole style tricycle (with electric motor assist). Built in crumple zones and protective cage should end this whole nonsense about “protected” bike lanes, because you’re traveling in your own one.

  29. You want to greatly reduce the incidence of cyclists getting hit from behind why not mandate that bicycles operated on roads must have working brake lights like every other vehicle is required to?

    I read some PHD-level research recently that said that combined median recognition and reaction time of all motor vehicle drivers to
    the onset of brake lights ahead was right around 1 second with a standard deviation of 0.3 seconds, whereas driver recognition and reaction time to a vehicle ahead slowing without working brake lights had a median of just over 3 seconds with a standard deviation of almost 1 second.

    Let’s say that we are doing just 30 mph. The difference between just the median recognition and reaction time with or without brake lights is about 88 feet. No wonder so many bikes get hit from behind. The same study also found that the human brain does not do as well seeing narrow bicycles from behind or oncoming nearly as well as seeing narrow bicycles moving at a sharp angle to the direction of vehicle travel.

    The #2 cause of bike accidents is the old right hook but every other vehicle on the road must yield to the vehicle ahead’s turn signal. For some reason some bicyclists don’t, putting themselves into the worst possible place, the driver’s right-side blind spot. Every car has a blind spot to its immediate right rear and so does every truck and bus.

    Older drivers also have a physical issue with turning their head to look in their right blind spot and must rely on their right-side mirror instead, which increases the size of the right-side blind spot and is often distorted by being convex, which reduces the apparent size of vehicles in the right-side mirror view. Convex right-side mirrors have been thought of by the US-DOT as being safer than flat right-side mirrors that increase the size of the blind spot even more, but they also reduce the chance that an elderly driver will see a bicyclist in their right-side mirror too.

    On a road-size 18-wheel truck of up to 72 feet in length, the immediate 12 foot width to the side of the truck is about 65% completely blind to the driver. Other drivers are instructed as part of their safety training to try to stay out of the big right-side blind spots of both buses and trucks.

    Why do some bicyclists feel that the big blind spot on the right side of trucks and buses should be their personal passing lane, as it is one of the least-safe places you can ride? In London, England there has been a bike safety campaign for the last few years where bike riders have been instructed to stay behind buses and trucks at red lights and stop signs rather than riding into the big blind spot both vehicles have. Why not do the same thing here in the US as it will cut way down on the incidence of bike riders getting run over by trucks and buses turning right, a simple and inexpensive solution?

  30. And if you had read the other studies I posted earlier you would have seen that the top 3 places that bikes get hit by motor vehicles are from behind at-speed, from behind when the bicyclist is slowing, and when drivers try to turn right with a bike alongside them in their blind spot.

    I am a 4 & 1/2 million mile retired professional driver, (about 3.25 million miles driving 18-wheel trucks over 31 years), with a recent Master’s degree in Urban & Regional Planning focused on Regional Sustainability and Sustainable Urban Transportation.

    Substantial peer-reviewed research says that both motorcycles and bicycles are difficult for following drivers to see, bicycles especially so. A motorist has a 300% better chance of seeing a bicycle moving sideways to the motorist direction of travel than motorists have of seeing a bicycle from behind.

    There has been a motorcycle safety campaign going for at-least 25 years now with the slogan “Start Seeing Motorcycles”. Perhaps that is what bike riders need, though my own professional opinion, both as a longtime professional driver and as an urban planner with 600-level bicycle planning taught by Denver’s Director of Bicycle Planning under my belt is that bike riders would be far safer riding on separate bike lanes/bike boulevards than they would be riding on attached bike lanes or sharrows.

    What happens when you are riding right next to an 18-wheel truck, a 10-wheel truck, or a city bus when a tire on the vehicle blows out? You don’t have to be within 5 feet of it to get badly hurt or even killed as heavy vehicle tires are 12-ply steel cord with 100 psi of air-pressure behind them. That 12-ply steel cord shrapnel will tear you to pieces being propelled outward by 100 psi air pressure. It is enough force to shatter an adjacent car window.

    If an 18-wheel truck blows a steering tire at-speed it might yank the front of the truck sideways several feet before the driver regains control. You don’t want to be right next to a truck or bus when this happens:

    A British video about truck tire blowouts that I think should be required viewing by those who insist on riding flimsy unprotected bikes on roads used by heavy trucks and buses:

    If you are riding your bike right next to a heavy truck when this happens, you are dead.

    Here is a blind spot turning accident in England where they have right-hand drive vehicles rather than left-hand drive like we have in the US. The same thing happens to bicycles here every day. Why try to pass a heavy vehicle on its blind side when its signal is flashing as the driver can’t see you there?

    Improving bicycling is just as much about improving bike rider skills and knowledge of all the reasons not to ride on highways with heavy traffic, not to ride too close to heavy trucks or buses, not to ride into blind spots where the driver can’t see you, etc.

    Here is protected bile lane design in downtown Denver where parked cars are moved outwards away from the curb and the bike lane is then moved between the parked cars and the curb. There are a few problems with this type of design though.

    #1: If somebody opens their passenger side door it is still possible to get doored.

    #2: The additional distance away from the travel lanes that bikes are riding makes it harder for the drivers of large vehicles to see bicycles in their blind spots.

    Don’t try to pass a truck or a bus on the side its turn signal is flashing-on as that will cut way down on right hook or left hook accidents. Don’t assume that the driver sees you.

    And do remember that brake lights on a bicycle would cut down following driver recognition and reaction time by an average of 2.2 seconds, or about 100 feet at 30 mph.

    Also remember that heavy vehicles can take 250% to 300% the distance to stop from the same speed as cars can, and that any vehicle with air brakes has air brake application delay of up to an additional half-second, on-top of driver recognition and reaction delay.

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