Following the death of cyclist Peter Wells (55) last November, the New Zealand Transport Agency had replaced a give-way sign with the new stop sign, and was investigating a permanent solution for the intersection.
Sgt MacAulay said drivers were "not complying with that stop sign", with many treating the intersection still as a give-way.
"Stop so your wheels have completely stopped moving. Then check to see if the way is clear," Sgt MacAulay said.
Police issued tickets to 25 drivers, including some for talking on a cellphone and for not wearing a seat belt.
The fine for failing to stop at an intersection is $150, and police would continue to monitor the intersection.