He put his name on the Omnibus Crime Bill- which was actually WRITTEN BY BYRD! By that time the tide was turning on the Exalted Cyclops. He knew if it was submitted, his active Klan membership would get it shot down. So he asked the little bigot he was mentoring to put his own name on it instead.
Byrd knew blacks in his party didn't trust him and might oppose it. So he got Biden to claim authorship. Everyone in WV knew that.