In this Tuesday, June 25, 2013, photo, a biker rides without a helmet on a Citibike, as part of New York City's bike sharing system, in New York. Under Mayor Bloomberg, the city has cracked down on ... more 
In this Tuesday, June 25, 2013, photo, a biker rides without a helmet on a Citibike, as part of New York City's bike sharing system, in New York. Under Mayor Bloomberg, the city has cracked down on smoking, fatty foods and sugary drinks for health concerns, but the nations largest bike-share program allow riders without helmets. (AP Photo/Bebeto Matthews) less 
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Associated Press | Photo By Bebeto Matthews
Sun, Jun 30, 2013 5:15 PM EDT