The incident happened around 4 a.m. on l’Eglise Road in St-Modeste, in Quebec’s Lower St-Lawrence region.
The man in his 40s suddenly veered off the road, resulting in a violent exit. He is now in hospital where his condition is considered "extremely critical," according to a Sûreté du Québec spokesman.
Provincial police are looking at whether speeding, drowsy driving or sudden illness played a role in the crash.
The man was wearing a helmet.