A bike-sharing craze that has swept China over the past two years is picking up speed in cities across the United States, but with a different spin as tough local regulations rein in the roll-out of dockless bikes.

Chinese startups pioneered dockless bike sharing: unlock a bike with your cellphone, ride it, park it, and relock it. But the downside has been bikes piled everywhere in many cities, clogging the sidewalks.

Many major U.S. cities have pre-empted that problem with rules that sharply limit how many dockless-bike companies can operate and how many bikes they can offer in an effort to avoid problems with blocked sidewalks.
More>>