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A new study looks at why bike share is so much safer than regular biking

Here's a remarkable fact: Not a single person has died using bike share in the United States.

Bike sharing has seen explosive growth since 2007, with systems in at least 94 cities and more than 35 million trips taken. There have been some serious injuries, yes. But — knock on wood — we've seen zero US deaths from bike sharing so far1. Contrast this with the overall estimated cycling fatality rate of 21 deaths per 100 million trips.

I should also mention that there has been one documented bike-share death in Mexico and two in Canada. But even those rates, the report notes, seem to be much lower than the estimated rates for cycling more broadly.

And that's not necessarily a fluke: Researchers have found that bike-share riders tend to get into far fewer crashes than other cyclists. A new report from the Mineta Transportation Institute sifts through data from bike-share systems in Washington, DC, San Francisco, and Minneapolis. They found that bike-share bikes had lower collision and injury rates than personal bikes in all three cities. In DC, the collision rate for bike share was 35 percent lower.

Intrigued by this, the report's authors interviewed both riders and a variety of experts from transportation departments across the country. They came to a few broad conclusions for why riding a bike-share bike seemed to be consistently safer than riding a personal bike:

1) The design of the bike matters a lot. Bikes in public bike-sharing systems tend to be heavier and feature wider tires, making them sturdier and better able to deal with bumpy roads and potholes (a leading cause of cyclist-only crashes). The bikes also have fewer gears and are incredibly clunky, making it hard for riders to go very fast. And they feature drum brakes, which work better when it's wet out.

(Bikesharing and Bicycle Safety)

On top of that, the bikes tend to be painted with bright colors and feature flashing lights, making it easier for cars to see the riders. And the seat forces the rider to stay upright — again, improving visibility.

2) Bike-share trips usually take place in denser, slower-moving urban areas. Bike-share stations are disproportionately concentrated in downtowns with lower average road speeds and lots of pedestrians — that is, places where drivers tend to be more alert. This matters: The authors argue that car-bike collisions become much more likely when cars are going faster than 30 mph. And driver inattention is a common factor in crashes.

3) Bike-share riders are less experienced — but that's not always a bad thing. "A few experts said that bikesharing tended to attract people who may be new riders to cycling or infrequent riders," the report says. "These experts said that users who were less experienced were more apt to be cautious, defensive riders and be risk-averse." (Not everyone agreed with this, though. Other experts thought that the inexperience of riders could sometimes be a hazard.)

4) Bike sharing is safer despite lower rates of helmet use. One thing we know is that bike-share riders use helmets at a far lower rate than regular cyclists. But that doesn't seem to make the bike-share bikes more crash-prone. Who knows? It might even help — people have argued about this for a long time. One hypothesis is that drivers behave more carefully around cyclists who aren't wearing helmets.

(That said, the authors do warn that there have been instances of serious, non-fatal crashes involving bike-share riders — including head and spinal injuries. And they point out that helmets help in these cases: "Helmets, like seatbelts in cars, mitigate the severity of injuries when a collision does occur, but they do not prevent the collision from occurring.")

5) It's not clear that bike sharing creates "safety in numbers." This was one surprising finding. Some transportation experts have long suggested there's a safety-in-numbers effect in biking — the more cyclists there are on the road, the more cautious drivers are. But the authors of the MTI report couldn't find much evidence for this in the data. In both the Bay Area and Washington, DC, overall collisions are pretty tightly correlated with the number of cyclists on the road. Maybe we haven't hit the tipping point just yet.

In any case, the full report is interesting reading. Among other things, there's a discussion of the pros and cons of building protected bike lanes and whether bike sharing has driven an increase in bike commuting. (It's a bit tough to say, since bicycle commuting seemed to be on the rise in Washington, DC, the Bay Area, and Minneapolis before bike-sharing systems were widely available.)

*Note: I should also mention that there has been one documented bike-share death in Mexico and two in Canada. But even those rates, the report notes, seem to be much lower than the estimated rates for cycling more broadly.

Go deeper:

  • Thanks to Adam Russell of Mobility Lab for first highlighting the study.
  • One common criticism of bike-share systems is that they mostly benefit wealthier white urbanites. It's a real issue. But here's why that's been hard to change.
  • Should bikes and cars share the same road — and the same rules?
  • A few years ago, Joseph Stromberg made the case that cities shouldn't force cyclists to wear helmets — on the grounds that it doesn't improve public safety.