The boy was hit at 3.40pm at the pedestrian crossing in Handsworth Road, Sheffield, outside the entrance to Asda on Friday afternoon.
The motorbike, which was carrying two men, did not stop at the scene and moments later was involved in a second collision with a red Audi A3 at the junction of Handsworth Road, Retford Road and Orgreave Lane.
One of the men on the motorbike, who is 22 and from Sheffield, suffered serious head injuries while the other man fled the scene.
The woman driving the Audi was not hurt.
The injured man has been arrested on suspicion of failing to stop at a collision and aggravated burglary.
A spokesman for South Yorkshire Police said: “It is currently unclear whether he was the rider or the pillion passenger.”
Sheffield South East Local Policing Team have said the injuries to the boy are ‘not thought to be life-threatening’.
Anyone with information is asked to call South Yorkshire Police on 101, quoting incident number 673 of Friday, May 13.