James Sera has become a five-time Australian karting champion after he finished second in KA3 Senior in the final round of the Australian Kart Championship, presented by Jayco and Castrol Edge at Todd Road.
Jack Bell won the final for the first time but second was enough to give Sera the title.
Scott Sorenson defended his national title with a win in the KA1 final, with his nearest rival Kyle Henry-Smith losing a wheel on the first lap.
Joshua Fife clinched the KZ2 championship as Pierce Lehane won the final, becoming the first driver ever to win finals in three elite categories of Australian karting.
TaG 125 produced a spectacular incident when rain hit Turn 1 midway through the final and caused half the field to crash out.
Joshua Car ultimately took the race win but finished second in the championship to Brendan Nelson.
The X30 title did go to Car as Leigh Nicolaou won the round, while Ryan Tomsett defended his crown in Cadet 9.
Fletcher Harris won the round in Cadet 12, but James Wharton had already wrapped up the title with a round to spare.
Broc Feeney clinched his first national title by finishing third in the KA2 final.
Jay Hanson won the KA4 Junior championship.