Neil Townsend, 32, became pinned under a semi-truck about 9 a.m. near the intersection of Wells and Oak Street. He was pronounced dead on the scene.
Chicago Police say Townsend was traveling southbound in the bike lane when the door of a parked car opened. The cyclist swerved and fell or jumped into the path of a southbound truck.
The truck driver stayed on the scene as did the Chicago man who opened the car door. He was given a citation for opening a door in traffic.
Police continue to investigate.
"A couple of seconds that you take can make the difference for whether someone goes home to their family or doesn't," said Ethan Spotts, Active Transportation Alliance R5, a biker advocacy group.
Nearby residents say the area is dense with cyclists and motorists.
"I just feel sorry for the people involved," said Larry Burns. "It's going to happen again. Sorry to say, but it's true. Bikes and cars and trucks and joggers and roller bladers, they don't need to be mixed."
"It's devastating. He probably didn't think he was going to have this kind of day. There's a family out there that's receiving news that they were not expecting, I'm sure," said Kim Francis.
Biker Charley Jordan says he's had two accidents where he says motorists were not watching out for bikes.
"I'm definitely stopping at the red lights, stopping at the stop signs and all the traffic laws just to make sure something like this doesn't happen," Jordan said.