There are calls for the rest of Australia to follow in the NT's footsteps and relax mandatory helmet laws after the country's largest bike riding organisation vowed to review its stance.

Bicycle Network, which has a membership of about 50,000 cyclists, recently published a survey that found 30 per cent of respondents would ride more often if helmets weren't mandatory.

It also found more than 60 per cent of cyclists believed they should be able to ride without a helmet if they wanted to.

Liberal Democrat Senator David Leyonhjelm, who is known for championing policies that reduce red tape, said this showed people believed in their own ability to assess the risks posed to them by helmet-free riding.

"It's true that if you fall off, land on your head and you're very unlucky you'll end up very severely injured," he told ABC Radio Darwin's Richard Margetson.

"But the chances of that occurring are absolutely tiny, and that possibility does not justify telling all the rest of us what's good for us.

"You guys in the Northern Territory are allowed that decision, you're treated as adults, while the rest of the country are treated as children. We can't make that decision for ourselves."

Fines for no helmet QLD – $126

QLD – $126 NSW – $330

NSW – $330 VIC – $198

VIC – $198 TAS – $100

TAS – $100 SA – $102

SA – $102 WA – $50

WA – $50 NT – $25 if you're under 17

Northern Territory bike safety laws don't require cyclists to wear a helmet as long as they're above the age of 17 and not riding on roads.

Senator Leyonhjelm said that with exceptions such as children and lycra-clad cyclists travelling at high speed, relaxing the laws would allow more people to jump on their bike more often.

"People say, 'Oh, the helmet, I can't be bothered fussing around with a helmet and finding the damn thing', and so they drive their car and miss out on exercise."

Long-held policy under review

Bicycle Network chief executive Craig Richards said the organisation was reconsidering its support for mandatory helmet laws.

It would be a significant change of tune, upending a position it honoured since the laws were introduced in 1991.

"Organisationally we have been strong supporters of helmets, but the question now is about whether helmets should be mandatory," Mr Richards said.

"That's something that we've opened up and had a good look at."

The network will comb through the literature before arriving at an official position in April, but conceded other jurisdictions could learn from the NT's relaxed approach.

"It's the only place in Australia where you don't have to wear a helmet at all times, and we've seen that it doesn't really seem to be as big an issue," Mr Richards said.

He also acknowledged arguments that strict helmet laws prevented people from taking a quick ride, say, to the corner store.

"One of the big arguments is around the number of people a helmet stops being physically inactive.

"The other argument, of course, goes it's also the government's responsibility to pay for the care that's given to people who suffer illnesses as a result of being physically inactive."

Senator Leyonhjelm admitted there was a limit to how much he could do to what was effectively a state and territory issue, but said he could put pressure on parliamentary colleagues responsible for coordinating COAG initiatives.