The bicycle, a simple machine that has remained largely unchanged for 200 years, has served as a tool of both freedom and oppression, ushered in the space age, been sexualized, demonized, mythologized, and is still, to this day, ridden by a huge swath of humanity. Today’s guest is Jody Rosen, a New York Times Magazine contributing writer, Brooklynite, and urban cyclist, who comes fully clipped-in to discuss all of the above: He is the author of the new book “Two Wheels Good,” out this week. Let’s ride.