Think you're safe riding in that on-road bicycle lane? You may be wrong.

Interviews with almost 200 riders hospitalised after a serious crash on their bike show one in five of them was in an on-road cycling lane when they were hurt.

Cyclist Conor Murtagh, who was left with fractured vertebrae last October when a car hit him while cycling in Carlton. Credit:Pat Scala

And the accidents occurred most commonly when a car was either turning into the path of an oncoming cyclist or when a vehicle driving alongside a rider turned left into their path.

The 186 cyclists who spent a night or more in The Alfred or Royal Melbourne hospitals following a serious bike crash agreed to take part in the study, led by Monash University researchers.