Shahum says San Francisco has many of the factors that have made Amsterdam so successful in encouraging bicycling, including narrow streets, similar population density and higher-than-average citizen participation:
"The two cities' most obvious difference is terrain. Amsterdam is as famous for flatness as San Francisco is for hilliness. Yet, I contend that in San Francisco we narrow that disadvantage with gears (almost non-existent in Amsterdam), bike racks on buses, and, the fact that most of us can choose to pedal around, instead of straight up, steep hills for many trips."
Shahum also found that bicycle culture is a relatively new phenomenon in Amsterdam, which is encouraging for changing opinions and habits in the U.S.