Two crashes on the same stretch of State Highway 1 at Mackays Crossing are impacting traffic heading north.

Glass has fallen off a truck and smashed on the road, closing the right hand passing lane.

Shortly after, a car hit a motorbike, causing moderate chest injuries to the rider.

Inspector Marty Parker said traffic isn't too bad, but they're working to clear the area.

He described it as a "double banger effect."

"We've got two crashes side by side and they're trying to clear the scene of the debris, the broken glass, and also tidy up this other crash."