More than 72 per cent of cyclists who broke the law last year haven't paid their fines, including 4449 people who owe more than $244,695 after being caught by police not wearing a helmet.

But offences by cyclists have dropped by 36.6 per cent since 2013, when there were 14,616 infringements, according to new figures. Police say this is thanks to more people using purpose-built cycleways.

Road policing operations manager Peter McKennie said the cycling infrastructure meant less risk of people being hit by traffic and so "we are less likely to press the enforcement in those environments".

Police have the discretion to charge and assess the risk of the situation. "We always encourage people to adhere to the law by using the appropriate lights on their bikes, wearing reflectorised clothing, having adequate brakes and wearing safety helmets."


Offences labelled "decision unpaid" means the fee is unpaid and referred to the Ministry of Justice.

Contrary to popular belief, it is not illegal to ride a bicycle after drinking alcohol.

In the Official Information Act response about cyclists' offending, Superintendent Steve Greally said it is not an offence to ride a bicycle intoxicated, but police "strongly recommend that people do not place themselves at risk by doing so".

Of 27 cyclists observed on Auckland's new Light Path, every rider wore a helmet and everyone spoken to had or would pay a fine.

A spokesman for the Ministry of Justice said fines for cycling offences were not treated differently from other infringements and border alerts could be put on the passports of anyone owing money.

As with any fine not paid within the allocated time, it is lodged with a court for collection and a cost of $30 is added to the infringement fee. There are 28 days to pay.

When enforcement action starts, another fee of $102 is added.

The spokesman said of all the unpaid fines in New Zealand, those owed due to cycling offences were an extremely small percentage.

Lads in Lycra are real alpha-males

Lycra-clad middle-aged men's attraction to cycling is linked to their alpha-male urges, a Kiwi sports psychologist says.

Campbell Thompson, who is preparing a number of sports teams for this year's Rio Olympics, will speak today on "The Psychology of the Mamil" at the Australian and New Zealand College of Anaesthetists' annual meeting. He reckons Mamils (middle-aged men in lycra) on suburban roads on weekends may be "sublimating primitive urges to mate and fight" by channelling their inner weekend warrior.

"The Mamil approaches recreational cycling in an intense and focused way," Thompson said. "Mamils are often highly motivated people who are putting that energy into a sport. He channels his 'weekend warrior', developing an almost professional level of competitiveness about what is a social activity."