"The (start) gate moved but it didn't drop straightaway and I was still on the gate. To ride from last place and get back into contention for the lead was good practice," Cooper said.
Cooper's late-2013 switch to the Honda Shop Racing squad has brought him under the wing of Tauranga's former MX2 world champion Ben Townley who manages the team.
"We understand each other and we work together well," said Cooper.
The win came a year after Townley retired from top level racing and marks his first major "off the bike" success in the in the sport.
Townley highlighted one area where Cooper has become a more complete rider.
"The big thing has been his consistency. We made a list of strengths and weaknesses before the season and our goal was make consistency part of his package."
Cooper will continue to have the world champ's guidance during the Australian series. Townley switches from the team manager role to work as a rider coach for Cooper and Josh Cachia, the Honda team's MX2 rider.
Taupo's Brad Groombridge (Suzuki) made a determined bid to reach second place in the MX1 class and won the final race, finishing one point behind Australia-based Scotsman Billy MacKenzie (Yamaha). Rotorua's Michael Phillips (Honda) was fourth in the series.
The MX2 title was won by Mangakino's Kayne Lamont (Husqvarna), who needed most of his big points to stay ahead of Hamish Dobbyn (Dargaville).
Lamont had his appendix removed on Thursday night and bravely made certain of the title with a fourth and third.
Dobbyn took the Taupo MX2 round win on a tie-break decider from Mount Maunganui's Rhys Carter (Suzuki), who ended a frustrating campaign with a final race win to climb back to sixth in the championship.
Hamilton KTM racer Josiah Natzke, 15, won the 125cc title winning all three races at Taupo and becoming the youngest-ever winner of a senior national title to beat Atiamuri's Hadleigh Knight (KTM) by 74 points.
Te Puke's Logan Blackburn (Yamaha) finished third in the 125cc title.
His bid for second place ended in race two at Taupo when he cartwheeled off his bike and sustained a broken collar bone.
Tauranga's Ryan Metz (Yamaha) finished fourth in his first attempt at the full series while Omokoroa's Aaron Wiltshier (KTM) returned after missing the previous round with a dislocated shoulder, finishing second at Taupo and climbing back to sixth in the championship.
