Bey was an outstanding amateur boxer who had taken up the sport to lose weight and eventually competed on the U.S. All Army Boxing Team.
He made his professional debut in 1981, defeating future undisputed world heavyweight champion James "Buster" Douglas by a second-round knockout.
He built up a record of 14–0, becoming the first man to stop the durable veteran contender George Chaplin (TKO4) as well as defeating future WBA heavyweight champion Greg Page (W12) to capture the United States Boxing Association heavyweight championship.
In March 1985 Bey was given a title shot by IBF heavyweight champion Larry Holmes.
Bey never regained his confidence, losing his USBA title by 11th-round TKO to Trevor Berbick in his comeback fight, then being relegated to 'opponent' status for the remainder of his career, matched against the likes of James "Bonecrusher" Smith, Joe Bugner in Australia, Tyrell Biggs, and Johnny DuPlooy in South Africa.