Traveling in the Realm of Very Big — and Very Small — Numbers

In the comments for the post How do we get from here to there? I asked readers to estimate how many miles they’ve biked in what they considered to be a “vehicular cycling” manner, and how many motorist-related crashes they’d experienced in those miles. Here are the results (which are of course not scientific, but still pretty darn impressive):

Fourteen respondents reported a combined 631,000 miles — and average of about 45,000 miles — with only two motorist-related crashes. So that works out to 315,500 miles per crash. Curiously, we had one major outlier who accounted for not only the most miles, but both crashes — and it was none other than Vehicular Cycling Grand Poobah John Forester, with 205,000 miles under his belt. With John’s numbers removed we get 426,000 miles with no crashes.

Also notable is that neither of John’s crashes involved overtaking motorists; one was a left-cross and the other a dooring (!).

Keri reported a crash in a bike lane before taking up vehicular cycling. While I reported 50,000 miles of vehicular cycling, I had another 100,000 miles before that of being a gutter bunny, and still managed to escape without a motorist-caused injury.  ChipSeal reported being right-hooked, but without a crash.  Rodney reported being run off the road a couple times, but we’ll cut him some slack with his mere 4,000 miles of experience.

(Bill Moritz of course did a self-reporting survey of experienced cyclists, but he didn’t ask people to differentiate between their “vehicular cycling” experience and their “other” cycling miles; neither did he ask for crash types.  On the other hand, he had about 2,400 respondents to our 14.)

Let’s play with these numbers a bit to put them into perspective (using the 631,000 miles and two crashes).

If we assume a cyclist travels at about 12 mph (reasonable when you consider urban/suburban cycling and traffic signals) that’s 52,583 hours of cycling; 26,291 hours per crash. 26,291 hours equals right about 3 years of cycling, every day, 24 hours a day.  Assuming a more realistic cycling schedule of one hour per day, 365 days a year, that’s 72 years between crashes.

And how many passing motorists does this involve? (Remember, none of our crashes involved overtaking motorists.) If we were passed by only one car every five minutes, that’s 630,996 passing cars (52,583 X 12). If we were passed once per minute, that’s 3,154,980 passing cars. (For those who do mostly urban cycling, the number is of course much higher than one passing car per minute.  You can do the math; just multiply 3 million by passing cars per minute.)  And gee, not one of those motorists was so incompetent as to hit a cyclist ahead of them on the roadway. If a motorist hits a cyclist from behind (assuming daytime or an adequately lit cyclist at night), he or she must be an exceptionally incompetent driver. (So shall we blame bicyclists for the existence of exceptionally incompetent motorists?)  In recent years cell phone use has become a major concern.  At times it seems that every third or fourth driver has a cell phone at his ear, yet even these compromised drivers manage to avoid hitting us.

In my crash data records for 2003 and 2004 for Metro Orlando, 62 of the 657 daytime crashes involved a roadway cyclist obeying the rules; of those only 22 involved overtaking motorists. What’s more, only two of those overtaking crashes involved incapacitating injuries (none fatal, 11 non-incapacitating, the rest “none, possible or unknown”).  In all but two of the 22 the crash report said it involved “Motorist Misjudged Space,” which is of course one of the key reasons we advocate lane control.

By comparison, there were 158 motorist-at-fault crashes involving daytime sidewalk cyclists, 15 of which involved incapacitating injuries.

In his latest column for Adventure Cycling, John Schubert noted that the US population is 300 million, so a 1-in-a-million event still results in 300 events, and 300 events spread around the Web and TV looks like an epidemic (see also “child abductions”).

Of course, for people who don’t understand risk assessment, these numbers are probably meaningless. Until we can get them out there experiencing it themselves, or at least seeing many others doing it, vehicular cycling and lane control will continue to be perceived as insanely risky.

Lane control does not require any exceptional physical skill.  Indeed it lessens the chances you will need to employ any exceptional bike-handling skills.  It is a choice one makes.  If you can ride a bike, you can do it.