A cyclist taken to Sir Charles Gairdner Hospital on Wednesday morning after collapsing on a Balcatta cycleway remains in critical condition with his family by his side.

Police sought the public's help to identify the man after finding him collapsed on the Reid Highway overpass near the Mitchell Freeway about 6.45am.

A man found collapsed while cycling has been identified. Credit:Michele Mossop

He was not carrying any identification and could not speak to officers.

The hospital has confirmed his condition as "critical but stable".

Police said the incident was medical in nature and no crime was committed.