Boy racers remain undeterred by penalties as they continue to use city streets as a race track.

On Monday, while Palmerston North Police acting Sergeant Mike Higgie was off duty and driving home, he found himself unwittingly caught in the middle of a drag race between mates on Rangitikei Street between Featherston Street and Tremaine Avenue.

The road was wet after the weekend's rain and there was a medium amount of traffic.

A yellow Ford Laser with a For Sale sign in the window, and black Mitsubishi Galant sat stationary at the traffic lights at 3.40pm. Both drivers were revving their engines and had a conversation between cars.

Sgt Higgie was in his private car behind the yellow Laser next to the third car, associated with the two in front, which was a grey Subaru Legacy.

"The windows were down and all four occupants were looking eager and chatting excitedly."

It was obvious a race was imminent, he said.

At the green light the two cars raced to the Tremaine lights and reached estimated speeds of more than 100kmh within seconds, Sgt Higgie said.

Meanwhile, the Subaru had sped to catch up, and all three cars were weaving dangerously within both north-bound lanes, he said.

He caught up to the speedsters at the Tremaine intersection and wrote down registration details.

"I'm just flabbergasted. This is the most blatant drag-racing I've ever seen."

He didn't phone for extra police assistance because it was all over within minutes and each car went its separate way.

Meanwhile, during the drag race, two pedestrians narrowly escaped being run over.

Both stood in the median strip to cross and stepped out in front of the drag racers anticipating enough time to get across.

"They were trapped with traffic coming at them on the other side," Sgt Higgie said.

They pair quickly jumped back after realising the cars were travelling at speed, he said.

Despite predominantly young men continuing to take risks with their lives driving, Sgt Higgie said the laws are tough enough.

Penalties for dangerous or reckless driving include three months' imprisonment, a fine of up to $4500 and disqualification from driving for six months.

However, speedsters' attitudes were slower to change.

"I don't think they're doing it specifically to annoy others, rather, it's to show off."

Driving modified cars meant drag racers can reach speeds of 160kmh to 200kmh easily, he said, which makes them near "impossible" to catch, he said.

"Most racers have police scanners so they know when we're on the way. Also the sheer volume of people makes it hard to find those responsible."

Driving in packs makes it difficult to catch all the culprits as they take different directions, he said.

Rangitikei Avenue has replaced Fitzherbert Avenue as a popular spot for drag racing.

Anywhere with double lanes suits drag racers, but

a speed camera near the bridge acts as a deterrent, Sgt Higgie said.

However, one motel owner near the Fitzherbert Bridge, who didn't want to be named, said some nights she lay awake waiting for a big crash. "It's quite scary at 2 or 3 in the morning on a Friday and Saturday night."

Rydges Coachman general manager Leonie Hateta would like to see another camera on Fitzherbert Avenue.

"Traffic lights aren't a deterrent they just speed between them," Mrs Hateta said. "I worry because there are schools and plenty of pedestrians around here."

Police have renewed an operation to check vehicles comply with the law, Sgt Higgie said. He asked anyone with information on the racing to contact him at 351 3600.

The cars involved include a yellow Ford Laser TX3, a black Mitsubishi Galant and a grey Subaru Legacy.