Nearly 9000 tickets have been issued to Hawke's Bay cyclists not wearing helmets in the past 10 years - amid calls by cycling advocates for a review of the law.
Local cycling advocate Vicky Butterworth said the first lesson she taught young schoolchildren about bike safety was the importance of helmets.
"Should you fall off, brain damage doesn't quite heal like bones do - that's what I tell kids.
"Whether you fall off on the road or you fall off on a concrete pathway ... your head is still vulnerable and it's really important that you protect that."
Just four months ago a 16-year-old Hawke's Bay cyclist credited her helmet with saving her from serious head injuries.
A collision with another cyclist near Whanawhana in July shattered Holly Atkins' helmet.
"It was really painful," she said at the time. "My helmet is broken into six parts. It was pretty much the only thing that saved me from some serious head injuries."
Police have issued more than 85,000 tickets nationally to cyclists not wearing helmets in the past 10 years. Fourteen cyclists have died on New Zealand roads and 332 have sustained serious injuries since January last year, NZ Transport Agency (NZTA) figures show.
Two of the dead cyclists were not wearing helmets.
Bicycle helmets were made mandatory in January 1994.
Non-compliance can result in a $55 infringement fee or maximum $1000 fine on summary conviction.
Cycling Advocates Network (CAN) spokesman Patrick Morgan said his organisation wanted the helmet law reviewed as it deterred potential cyclists. Cycle lanes and vehicle speed reduction were more important priorities, he said.
Mr Morgan obtained an exemption to the helmet legislation on medical grounds armed with a doctor's certificate in 2004.
He wears a helmet only when he deems there is sufficient risk. "It's kind of like if you imagine a car racing driver. They'd probably wear a helmet because they're doing a high-risk thing, but when you drive down to KFC you probably wouldn't bother."
NZTA spokesman Andy Knackstedt said exemptions could be given on religious or medical grounds. Nearly 150 exemptions - four this year - have been granted since the law was introduced.
The origins of the helmet law were widely attributed to the campaigning of Rebecca Oaten, dubbed the "helmet lady", in the late 1980s. Ms Oaten campaigned for helmets to be made compulsory after her son, Aaron, suffered permanent brain damage when he was hit by a car while riding his bicycle to school in Palmerston North in 1986.
Ms Oaten said a doctor at the time told her Aaron would "almost certainly not have suffered brain damage" if he had been wearing a helmet. Aaron died in 2010 aged 37.
A New Zealand medical journal article published in February found New Zealand's bicycle helmet law had failed in aspects of promoting cycling, safety, health, accident compensation, environmental issues and civil liberties. The article estimated the law cost 53 lives each year in premature deaths due to a corresponding reluctance to cycle and lack of exercise.
A 2011 Ministry of Transport survey found 93 per cent of cyclists wore helmets. The ministry advises that helmets reduce the risk of brain injury by up to 88 per cent.
Tickets issued