The crash happened in the evening on Jan. 27 near 5th Street and Eucla Avenue, according to the Los Angeles County Sheriff's Department.
Newly released video shows the victim, identified as a 37-year-old man, riding his bicycle along the curb when he was struck by the vehicle from behind. Deputies say the driver of the truck briefly stopped but then took off.
The victim suffered major injuries and was taken to a hospital.
Investigators believe the dark-colored pickup truck is a Dodge Ram, but other details weren't disclosed.
Anyone with information is being asked to contact authorities at 909-859-2818 or 800-222-TIPS.