It is a solid start for Gibbs in his title defence, with just three points his deficit to Cooper, and equally it was a positive performance from Lamont, still on the comeback from an injury sustained in November.
The riders will now move on to round two in Rotorua in two weeks' time, the track a happy hunting ground for Gibbs, who won the corresponding event there last season.
"I'm feeling really good on the bike. Today was decent, but off the start in the last MX1 race I got sideways out of the gate and dropped the bike. I was dead last," said Gibbs.
"The first three lap was just me trying to force past all the other riders. When I found my groove, I felt this was the best I'd ridden all day. To go from last to finish second in that race made me pretty happy."
Meanwhile, in the MX2 class races, Purvis had his work cut out battling fellow international stars Hamish Harwood and Australian Wilson Todd.
Purvis convincingly won the first MX2 class race of the weekend, his riding style as smooth as it was fast, reminiscent of his performance at the same track two weeks earlier, when he had won the MX2 class at the annual King of the Mountain Motocross.
But Australian MX2 champion Todd won the next race and defending New Zealand MX2 champion Harwood won the final race of the afternoon.
Purvis had to pick up the scraps after becoming tangled in traffic, the teenager eventually fighting through the congestion to finish sixth in race two and then third in race three.
Harwood has a nine-point lead over Todd and Purvis, the two riders in equal second after their mixed bag afternoon.
Altherm JCR Yamaha Racing Team manager Josh Coppins was both satisfied and disappointed with the results achieved by his riders.
"It wasn't too bad, but it should have been better," he shrugged.
"Max made a little mistake in his second race, which cost him. And Kirk made a mistake in his last race which cost him. Kayne was solid all day, especially given where he came from with not having the fitness. Overall I guess we can be content.
"From a team point of view, I think we nailed it. I personally think it's now up to the riders from here on. The bikes are good, but the riders need to execute things a little better and make fewer mistakes.
"To be honest, I expect all three to be on the podium. Out riders are top riders in their respective classes. I don't expect to be off the podium with our guys all series. On the podium is acceptable, but the top step is where we want to be," Coppins concluded.
