Karika made his debut in first-class rugby as a flanker for the Hawke's Bay team in 1992. He scored two tries in his first season.[1] In the 1997 season he began playing for the Central Vikings, a combined team of Hawke's Bay and Manawatu.[2] He was in the team that played the Vikings first ever game which was against the touring Fijian team.[3] Towards the end of the 1998 season, he tore two-thirds of the ligaments off his left thumb in a round-robin game against Nelson Bays and was out of play for the rest of the season.[4]
Karika was noted for his ability to outplay more established opposing openside flankers, despite being a lot shorter and a lot lighter than most flankers. His defensive work rate and ability to force turnovers was frequently recognised by rugby journalists.[5] He had the nickname "Turbo" and played internationally for the Cook Islands team in the late 1990s, including qualification matches for the 1999 Rugby World Cup.[6]
After retiring from playing, Karika was a development team coach for the Hawke's Bay Rugby Union.[7]
His daughter Sarah won the gold medal for the under-19 girls beach relay team at the 2011 national surf lifesaving championships.[5]