Right now, we know shockingly little, aside from the self-reported statistic that 6 percent of Portlanders use their bikes to commute. Our knowledge is captured only in tiny snapshots like the small wires set over bridge routes that count cyclists. Or Portland's "bike count," a citywide effort to hand-tally riders at select intersections for two hours on a single summer day. That glimpse costs 560 hours of city staff time and hundreds of volunteer hours.

"I have a staff person that spends all summer coordinating volunteers with pens and papers," says Margi Bradway, active transportation division manager for the Portland Bureau of Transportation. "We have a lot of people standing on street corners doing little marks every time somebody rides by."

If his idea works, Henderson's Ride technology will run cheap enough that sensors could conceivably be placed all over town. Each sensor, designed to look like a traffic reflector in the pavement, detects when a truck, car, bike or pedestrian passes by, and stores that information on a tiny hard drive. 

The sensors would be fast and reliable, precisely because they don't require an active Internet connection to record data. However, to upload that information from the sensors' tiny hard drives, the system relies on people periodically passing by with a "Ride" app running on their iPhones. The sensor piggybacks on the phone's Internet connection to beam ride information to the cloud.

The Ride app also tracks the individual routes cyclists take as they commute or run errands in the city, and asks how they feel about it. When their wheels stop turning, Ride prompts them to rate the journey as good or bad by clicking a "thumbs-up" or "thumbs-down" icon, then aggregates that data in the form of a city heat map. Red, yellow and green lines show which routes and city streets were rated favorably. Unsurprisingly, the downtown area was a glaring red grid.

"The [sensors are] more traditional, but they're not telling you anything about the person," Henderson says. "What kind of rider are they? Why do they ride? How do they feel about the ride they're taking? The app is about giving you a sense of depth."

A thumbs-down may not seem particularly telling, but Henderson can extrapolate from there. If a rider consistently reports "bad" rides on busy streets, it may be safe to assume that person is less comfortable with car traffic than other riders. And if riders create profiles, the data becomes richer.

Everything collected by the bike counters and Ride is placed into a database. The aim is to make this information publicly available on the Web and digestible, so anyone from activist to bureaucrat can understand and use it. So when East Burnside Street narrows to one lane westbound, or Southeast Division Street car traffic spills into the Clinton bikeway during construction, the city could conceivably see the effects on cyclists and pedestrians in real time—and possibly respond.

"What we want is a tool that is as easy to use as Google Maps, but has the ability to answer fairly sophisticated questions," Henderson says. As of January, Henderson and his team locked in a deal with PBOT to pilot a network of up to 100 bike counters across the city starting this summer.

The comparably low cost is one reason the city bet on Henderson. The bike-counting pilot is funded by $35,000 from Mayor Charlie Hales' "innovation fund"—which fronts money for Portland agencies to test risky ideas that may save money in the long term—and $5,000 from PBOT's budget. This will cover the cost of the sensors, their installation and staff to run the program. By comparison, the Hawthorne Bridge electronic bike counter, which Cycle Oregon donated in 2013, cost $20,000.

"This is why the mayor's innovation grant is so important," Bradway says, "because it allows us to try something we may actually fail at. And that's OK."

Henderson, lanky and clad in an oxford shirt the color of eggplant, looks like he could have been James Van Der Beek's hair double on Dawson's Creek. He dropped out of Reed College twice before eventually earning a math degree there, then wound up in Silicon Valley working as employee No. 13 at Square—the company behind those white flat screens that take your credit card at coffee shops. After moving back to Portland, he quickly made half a million dollars in revenue inventing Knock, a little app that lets you unlock your Mac by knocking twice on your iPhone.

"We had this success, and it allowed us to finance the business for another six months before we have to worry about revenue again," Henderson says. "I just had a kid, so I was thinking somewhat existentially, and thinking about what do I really want to do?"

For Henderson—a daily bike commuter with rain pants in his pannier to prove it—that was using Knock's Bluetooth technology to help the city gather complete bike data.

"You have this engineering mentality," Henderson says, "and after you've been doing it for a little while, you realize you can solve problems, but just because you're solving a problem doesn't mean you're actually doing the world a favor. You have to seek out the problems that matter.”