Motorbike rider 'in F-word road rage attack on elderly driver'

A violent road rage attack has been captured on camera in Sydney's west.

The vision appears to show a motorbike rider smash the window of a van - accusing the driver of cutting him up - before knocking him to the ground.

The rider can be heard using the F-word, claiming the driver's actions forced him on to the footpath.

The alleged victim is 75, and suffered grazing as he fell to the ground.

A passer-by filmed the bust-up in Lalich Avenue, Bonnyrigg, around 5pm yesterday.

Police are investigating and say they will speak to witnesses and the alleged victim later today.