With his mutant power of technopathy, Bolt could control electronic devices with his mind. He would use this ability to disable enemy electronics or re-enable them if they were shut off to impede his team. After Wolverine quit, the other members of Team X would also go their separate ways and Bolt made a new life for himself in Ohio.
In 1979, six years after Team X was disbanded, Bradley was making a living ripping of carnival patrons by using his mutant abilities as part of a sideshow attraction. One night, he was visited by his former teammate Sabretooth. Bradley knew what was coming and told Sabretooth that he wasn't afraid of dying. Sabretooth merely replied "Why? You haven't tried it yet?" before savagely mauling Bradley.
Bradley's death isn't shown on-screen, but upon his death all of the lights and electronic toys in his trailer turn off.