He's 7 1/2 and it's about time.
A couple years ago when all his buddies were learning to ride bikes we asked him when he wanted to learn, and his reply was, "but why would I want to ride a bike when cars are much faster?"
A totally typical Zane comment.
We laughed our heads off.
Later he declared he was going to be "a skateboarder guy & a scooter guy, but not a bike guy".