City bike share programs are a lot of things: Convenient, green, good exercise. But they don't jump out as particularly safe (no helmet, no bike -- no problem!) But three transportation experts recently confirmed that there have been no fatalities in 36 city programs since the first program was launched in 2007 in Tulsa, Okla.

The programs are found in Washington, Portland, San Francisco, Minneapolis, Tampa and many other urban spots.

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In New York, doubters predicted mass injuries, wrecks involving novice riders and worse. Reports Reuters:

At the time, then-city Comptroller John Liu called for mandatory bike helmets for adults to lessen "the human toll" but failed in his effort. "The Daily Show" host Jon Stewart joked that the bike share program sparked a new business idea called "Jon Stewart's Street Brain Removal Service."

And yet after 10.3 million trips in New York, just 40 people have needed medical assistance.

Experts say the programs are successful because the bikes are big, lumbering and not particularly fast. Again, from Reuters:

"The bikes are heavy, with a very low center of gravity, wide tires, drum brakes that keep the braking system dry even in inclement weather, and the bikes are geared so it is difficult to gain considerable speed," said Susan Shaheen, co-director of the University of California at Berkeley's Transportation Sustainability Research Center.
"It's like pedaling a tank," said Thomas Brereton, 53, an accountant from suburban Westchester County who rides a Citi Bike from the Manhattan train station to his Brooklyn office.

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Weirdly, this safety record does not apply to cyclists at large. In New York alone in 2012, 18 people died while they were cycling. In 2013, 12 died -- and the same number have already died this year in bike accidents.

"I believe that to be a phenomenal safety record and, coupled with the no U.S.A. fatalities, bike share has a better record than bicycling," said Russell Meddin, founder of the Bike-sharing World Map.