Is it abandoned? Maybe someone is hiking nearby. Perhaps it’s a “bait bike”, set to snare a would-be thief? Turns out it’s part of a bike share program from a company called Ofo.
Ofo is a dockless bike-sharing program. If you find one (I’ve seen two so far), you can unlock it with an app, ride it anywhere you like (for $1 an hour), and leave it anywhere (safely and legally). Each bike has a QR code, and a wheel lock that prevents rolling until unlocked with the Ofo app. You can also use the app to find nearby bikes.
According to @ofo_bicycle (ofo.com), there are 10 million of these yellow bikes around the world. The program was just introduced in the U.S. in August 2017, in 20 cities. And Ofo plans to rapidly expand across North America. So keep an eye out for all these yellow bikes!