Kamo's score of 166 gave City a chase of 105 that could have caused some real headaches.
But through Bert Horner (23), Joey Yovich (49) and James Thompson (26 not out), City cantered to the total two down going at better than a run a ball.
Thompson ended both innings unbeaten after scoring 69 on the first day.
The outright win for City was vital to their fortunes in the competition as leaders Onerahi Central also picked up an outright win.
Whangarei Boys' High School First XI started day two of their clash with Onerahi Central at 69 for four, holding a lead of just 10 runs.
Further hurting their chances was losing wicket keeper Rory Christopherson to Northland Men's duties, who was unbeaten on 36 at the close of day one.
Like Kamo, WBHS' middle order all got starts but couldn't kick on as quick bowler Tom Herman (4 for 30) again caused trouble.
Herman ended with impressive match figures of eight for 50.
Rory Anders (3 for 30) also impressed with the ball as they reduced WBHS to 109 for seven, before the pairing of Cullen Lowe (31) and Ian Osbaldiston (45) put on a vital stand worth 81 runs.
Herman and Anders then accounted for the final three wickets as WBHS were dismissed for 194, leaving Onerahi Central a chase of 135.
Onerahi Central started their chase strongly and didn't ever look back after an opening stand of 65 between Travis Keep (32) and Fletcher Coutts (57 off 46).
Tom Keogh also chipped in 19 as Onerahi Central chased down the target with seven wickets to spare, maintaining their winning start to 2017.