Where did Bam Margera get his name?

Answer 1

His grandfather nicknamed him "Bam" at the age of three after his habit of running into walls. His real name is Brandon Cole Margera <---yes this is true that he was born with this name, but he did legally change his name to "Bam"

Answer 2

Brandon Cole Margera, better known as Bam Margera, was born on September 28, 1979 in West Chester, Pennsylvania, to April Margera (née Cole) and Phil Margera. He was given the name Bam at age three, by his grandfather, after his habit of running into walls. He is of Italian (from his paternal grandfather), German, English, and Welsh descent.