Despite his success in the world championships, Pomeroy accepted a contract offer to race for Honda in the AMA national championships in 1977. He began the season by finishing second to Bob Hannah in the 1977 Supercross championship and, followed that with a third-place finish in the 250cc national championship final standings behind Tony DiStefano and Marty Smith. Also in 1977, Pomeroy became the first American competitor to win a moto at the 500cc United States Motocross Grand Prix. Following an injury plagued season in 1978, Pomeroy returned to Europe in 1979 to compete for Bultaco in the world championships. Unfortunately, the Bultaco factory was experiencing financial difficulties and closed a few months later. He then switched to compete for the Beta factory team however, their motorcycle proved to be too fragile and unreliable for the rigors of world championship motocross.