They began the 65-mile trek to the Atlantic City Boardwalk at 6:30 a.m. at the Ben Franklin Bridge.
One of the riders, 90-year-old Joe Paoletti of Langhorne, Bucks County, was taking part in his 15th Bike-a-thon.
The World War II veteran says he does it for a number of family members who have had cancer, but most especially for his granddaughter, who lost her battle with the disease.
"My young granddaughter who was age 11 at the time she contracted cancer, so I started riding for her. When she was 17, she passed away. She was very close to me. She and her mother lived with me in my home," Paoletti said.
The 90-year-old Paoletti bounced back from a serious bike accident to make this year's ride.
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