The incident occurred yesterday at approximately 10.30am when a 39-year-old cyclist was hit by a black saloon car on Swans Nest Road.
According to Gardaí a number of men got out of the car and assaulted the injured man with unknown weapons before the men left the scene in the same car.
The man was taken to Beaumont hospital where his injuries are being treated as non-life threatening.
Gardaí are appealing for any witnesses to the assault in particular anyone who may have dash cam footage, who was in the area at the time of the incident.
They can contact Gardaí at Raheny Garda station on 01-6664300, the Garda Confidential Line 1800 666 111.