A Park Ridge man has been charged with reckless homcide and aggravated drunken driving in the death of Robert "Bobby" Cann as he rode his bicycle Wednesday in Old Town, as the biking community is set to memorialize Cann in the monthly Critical Mass bike ride.

Cann, 26, who worked at Groupon Inc. on the Near North Side, was an avid bicyclist killed as he rode in the 1300 block of North Clybourn Avenue about 6:35 p.m. when a southbound Mercedes sedan struck him, authorities said.

Ryne San Hamel was charged this afternoon with reckless homicide, felony aggravated driving under the influence involving a death, and other misdemeanor charges, according to police. He is scheduled to appear in Cook County bond court on Saturday.

Cann, of the 3200 block of North Southport Avenue, was pronounced dead at 7:05 p.m. Wednesday at Northwestern Memorial Hospital, according to the Cook County medical examiner's office.

San Hamel had a valid license at the time of the crash, and does not have a significant history of sustained traffic tickets, with only one citation, a 2010 ticket for disregarding a stop light or stop sign, on his permanent record, officials said. He was, however, cited in 2003 for carrying alcohol in a vehicle, although records indicate the ticket was not sustained.

Thursday afternoon, friends gathered at the site of the collision and set up a small memorial. Today, many of his friends were joining the monthly Critical Mass bike ride as it rides past the same spot late this afternoon, friends said.

On Thursday, before they gathered on Clybourn, friends said they saw Cann’s willingness to help in work and in his social life.

Margaret Kizior, who met him while they were both working at REI, an outdoor equipment store at 1466 N. Halsted St., several years ago, said Cann would go out of his way to help anyone interested in biking in the city.

“Anytime anyone came in to REI and wanted to talk about biking in Chicago … he was really excited to get them into the sport and be safe in Chicago,” Kizior said.

“He was just my go-to guy for everything biking,” said Philip Bird, 29, who also met Cann at REI and became close friends with him.

Cann always made anyone he met feel at ease, said Kizior, 38.

“If you walked into a party and you didn’t know anyone, he’d be the first person to walk up to you, and you’d be best friends by the end of the night,” Kizior said.

Bird and Cann bonded over both being East Coast transplants, joking over Midwesterners’ accents even as Bird began to taken inspiration from Cann’s avid cycling.

“Every winter, I think about not riding, and then think, ‘What would Bobby do?’” Bird said.

Though not the type of bicyclist to weave in and out of traffic or blow off stop lights and stop signs, Cann participated regularly in the monthly Critical Mass bike ride, in which bicyclists gather at Daley Plaza and ride through the city en masse, friends said. Kizior, who last saw Cann at the Chicago Ride of Silence, a memorial for people killed while bike riding, noted that Cann always wore his helmet.

Julie Dziak, a nurse who drove by the scene just after the crash, jumped from her car with a towel and sweatshirt and tried to start emergency care.

She tried to stop the bleeding from a leg wound, and then began CPR, Dziak said Thursday night in an email.

Although she works in a neonatal intensive care unit, she was able to use her Basic Life Support training to continue chest compressions while other passersby kept his airway clear -- but she wished she could have done more.

Paramedics quickly arrived at the scene and took over.

"I just wanted to share and reach out to Bobby's family and friends somehow and let them know he was not alone," Dziak said.

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