For many Supercross fans, it’s a very much overdue update. Don’t Miss: James Stewart Retired. Stewart has woken up his dormant Instagram account after almost 12 months to announce he’s ready to reveal all and it will have Supercross fans waiting with … James Stewart Jr. is an American Professional motocross racer who has a net worth of $20 million dollars.James Stewart Jr. is also known as Bubba Stewart. He is a racer competing in supercross, currently not very active.