United Kingdom, Oct. 16 -- Billy Joel has been banned from performing and is "not allowed to drive" anymore.

The 77-year-old musician has revealed he is selling off his beloved collection of motorbikes because his doctors have warned him against getting back on the road since he was diagnosed with normal pressure hydrocephalus (NPH), a neurological condition that occurs primarily in older adults, and they have also ordered him to stay away from the stage because the "stress of the show" could be too much for him.

Billy told The Hollywood Reporter: "Well, my health is good. I have this thing called hydrocephalus. It used to be called water on the brain, so it affects your balance, it affects your memory, it affects your vision, your hear...