One of the first things you might see in Manly, home to some of Sydney's most popular beaches, are groups of carefree teenagers in swimwear riding illegal e-bikes.
Weaving in and out of traffic and careening along footpaths, they're an increasingly familiar sight, infuriating many locals.
"I see the kids riding on the road, I see them riding without helmets. They're clearly not subject to the same strict rules that other modes of transport are," says Chris, as he heads home after a swim.
"One kid was explaining to me how they can jailbreak them and remove the speed limits and make them go three times the speed they're supposed to."
Residents of some of Sydney's wealthiest beachside locales, stretching from the Northern Beaches through the eastern suburbs that take in Bondi and down to Cronulla in the south, say the number of teens riding e-bikes has exploded in recent years.
Those favoured by teens are also known as fatbikes due to the thick tyres meant for tackling sand and off-road terrain, and are often illegally modified to allow them to travel at far greater speeds than the 25km/h limit for e-bikes.
They have been hitting the headlines as hospitals report huge jumps in e-bike-related injuries and critics say police are failing to enforce existing laws to keep roads – and footpaths – safe.
Food delivery riders on fatbikes are also a source of frustration for many Sydneysiders.
But in recent weeks teens have attracted wider attention because of viral videos.
One shows dozens of teens motoring over a pristine golf course near Manly, and another shows a huge group, including teens in school uniform, doing wheelies across the Harbour Bridge during a "mass rideout" led by a US YouTuber.
Teens have also been videoed riding through shopping malls and taking over whole lanes of traffic, while councils have been inundated with complaints from pedestrians and motorists.
"Sometimes I ride at 50 or 60km/h [on my Vespa] on Pittwater Road and they overtake me on the footpath," says Northern Beaches local, Andre.
"They're like mini motorbikes," adds Debbie, who says she and her dog have been "taken out" a number of times by children on fatbikes.
Getty ImagesAs I step into a Manly side street, I nearly get mown down myself by two teens on fatbikes, each with a pillion passenger, speeding the wrong way down a one-way street.
Of the 750,000 e-bikes on New South Wales roads, the state government estimates the number of illegal fatbikes to be in the tens of thousands.
"I compare it to Covid," says Harold Scruby, the chairman of the Pedestrian Council of Australia. "It starts here and if they don't put a stop to it…" he trails off as he contemplates the apparently inexorable spread of teenagers on illegal fatbikes.
While e-bikes have caused headaches for authorities around the world, the illegal fatbike trend seems to have particularly taken off around Sydney's beaches.
Observers say it's because of a combination of good bike-riding weather, parents with deep pockets – the cheapest model of one of the most popular brands retails for a minimum AUD$3,000 (US$2,110, £1,579) - and a lack of reliable public transport.
"It's a lifestyle thing too," Scruby says. "Kids love going to the beach on them."
But lack of regulation also plays a role.
There is no minimum age at which children can ride e-bikes and under-16s are allowed to ride on the footpath – sometimes putting them in conflict with pedestrians.
Police say it is difficult to catch teens because if they give chase they risk causing an accident – a problem I discovered for myself when I set out to interview them.
One I do manage to speak to, Robert, a 14-year-old who's just been for a swim, says he loves his fatbike for the freedom it gives him but he has "kept it legal" and doesn't do "stupid" stuff.
"My dad said if the cops take it then you don't get anything back."
Scruby says the number of illegal e-bikes began to rocket three years ago, not long after the federal government loosened import restrictions in 2021. Importers no longer had to prove that e-bikes came up to minimum safety standards.
Then in 2023, the state government of New South Wales, of which Sydney is the capital, doubled the maximum power wattage allowed for e-bikes to 500w.
E-bikes should require riders travelling at more than 6km/h to pedal and the motor should cut out completely when they reach 25km/h.
But retailers could import high-powered bikes and give buyers a PIN to "unlock" them, allowing it to reach higher speeds supposedly only on private property – a crucial loophole.
"Unscrupulous marketers suddenly realised every kid in Australia is going to want one of these," Scruby says.
Helen LivingstoneTeens aren't the only ones who love e-bikes.
At Bondi Beach, Will is loading his daughters, aged six and eight, into a kid trailer on his e-bike after their daily swim, his surfboard attached to the side.
"We use it every day, it's really good with little kids," he says. They can zip to and from the beach without worrying about parking. He's not overly concerned about teenagers on overpowered e-bikes.
"I mean I'm envious, I wish I could pop a wheelie like that. I'm just thankful I don't have boys that age."
Scott Jeffery, who runs an e-bike shop, says they have many advantages, chief among them that they allow riders to travel further and climb hills more easily than a push bike.
"They should be used in many circumstances in place of a car," he says, which has environmental benefits and advantages for older people, who can no longer keep up with their riding buddies or drive.
"It becomes their main form of transport," he adds.
The teens who are out riding on golf courses and such are "foolish and it's ruining the whole usage of e-bikes for everyone else."
It seems to be doing more than that.
Injuries caused by e-bikes are becoming "almost business as usual" in paediatric and adult major trauma centres, says Dr Brian Burns, a trauma specialist at Sydney's Royal North Shore Hospital.
"You're almost on something with the equivalent speed of a motorised vehicle, but not wearing a motorbike helmet," Burns says, noting that motorbike riders typically wear other protective gear such as leathers and gloves.
Doctors are increasingly seeing "significant brain injuries" as well as lesser, but still serious, injuries like friction burns, he says.
Pedestrians are also at greater risk from e-bikes than push bikes. "Sometimes they're about 30, 40 kilos, and you've got a teenager or two on them," Burns says.
St Vincent's Hospital Sydney last month said the number of serious injuries from e-bikes treated at its emergency department had doubled in 2025 compared to the previous year and spiked by 350% since 2023.
Observers say teens also don't fully realise that they are at risk of criminal charges.
In Queensland, an 8-year-old riding an illegal e-bike died in October after crashing into a 15-year-old who was also riding an illegal e-bike, though the teen's was higher powered and the younger child was not deemed to be at fault.
The teenager now faces charges including dangerous operation of a vehicle causing death as well as driving an unregistered and uninsured vehicle.
Helen LivingstoneFaced with the prospect of similar incidents in NSW, the state government recently announced a raft of proposals - a minimum age for e-bike riders, European safety standards for e-bikes, which must have a maximum power output of 250w and anti-tampering protections, and they said police would begin crushing illegal bikes.
"We want Sydney to be a cycling city at the same time as wanting to have some control over how bikes roll out," NSW Transport Minister John Graham told the BBC.
But these plans haven't pleased everyone.
Jeffery says the government's "knee-jerk" response is over the top. "Educate them first and then go on to enforcement."
Scruby says the government hasn't gone far enough: 16-year-olds would still be allowed to ride on footpaths and the government has not addressed the question of insurance, which leaves anyone who is hit by an e-bike and seriously injured unable to claim compensation.
"The main problem here has been that technology has just outpaced the law at 100 kilometres an hour," he says.
"The genie's out of the bottle."
