"I really felt good at Motueka. I came from behind in all my races and, with Josh taking different lines to me, I just decided to let him go in the last race.
"I think I have the wisdom now to protect my championship and not throw anything away."
Meanwhile, Queenstown's Scott Columb continues to dominate the senior lites (250cc) class, finishing 1-2-1 in his three outings to keep Australian Honda star Geran Stapleton at bay.
In the junior lites (250cc) class, Timaru's Josh May (Honda) was again a force to be reckoned with, finishing 1-1-2 and once more eclipsing Wellington's Josh Bartosh (Honda).
Hamilton's Josiah Natzke (Yamaha) was simply too good for his rivals in the junior lites (85cc) class, scoring a hat-trick of wins over Southland's Kyle Hartley.
Sponsored by the Backflips clothing company, this year's championship wraps up at Taupo next weekend.