For years the young mothers of Japan have held their tongues as the country's silent minority but now they have been pushed too far. In open revolt at the Government, their demands are simple: sell us cheap tricycles or leave us alone.

Faced with draconian new cycling laws and the effective criminalisation of their daily school run, the mothers have unleashed their most powerful weapon. In a country already suffering the lowest birthrate in the developed world, young women are threatening to stop breeding beyond their first child if the tradition of sannin-nori — or “three-on-a-bike” — is outlawed.

Their surprisingly fierce rebellion scored an instant hit. Yesterday, confronted by the “nuclear option” of Japanese demographics, the National Police Agency began to back-pedal, yielding nervously to the force of collective maternal fury.

Police have said they will not enforce the ban if the mothers are able to show that they are “riding safely” — a comment that suggests they may still get tough with offenders.

The situation focuses on a recent government decision to review the Road Traffic Law for the first time since 1978. Cyclists, who regularly — and legitimately — use the pavements rather than risk the lunacy of Japan's crowded roads, were targeted heavily by the legislation.

Many of the new rules are an attempt to tighten up safety, by banning the use of mobile phones, iPod-type music players and the carrying of open umbrellas.

In response to rising levels of cyclist-on-pedestrian accidents — 11,000 incidents since 2003 — the pavements are also to be off limits.

All of that might just have been acceptable but the law extended to a ban on sannin-nori, the precarious practice whereby a mother transports two children on a single, sturdy workhorse bicycle known universally as the “mama-chariot”.

The mama-chariot is more than a machine; it is an institution. Where Britain has the Chelsea Tractor, Japan has its armies of bicycles with one child in the front basket, one on a seat at the rear and a mother pedalling between them.

Most know perfectly well that sannin-nori is dangerous but say that they have little choice. It is only practised by mothers of very young children — once they reach primary school age they must find their own way to school.

Most kindergartens in Japan, however, ban mothers from bringing their children to school by car, and to defy that would be to risk ostracism. With their bikes banned, say the mothers, they have no way to transport their broods. The mothers have directed their outrage towards the National Police Agency. But yesterday's concession does not end their plight fully.

One official suggestion has been that sannin-nori could continue if the mothers used more stable tricycles. That suggestion has only fanned their anger because the cheapest tricycle available costs about £500 — ten times the price of a perfectly good mama-chariot. Bring the price of a trike down and we will change our ways, say the mothers at the school gates. Until then, expect to see us riding sannin-nori in our thousands.

On Your Bike

— Bicycles, known as jitensha or by the slang term charinko, are extremely common in Japan. The first Japanese-made bicycle was built from rifle barrels by a gunsmith in 1892

— The vast majority of modern bicycles are made to a standard design incorporating a basket, a child seat, a kick-stand, a built-in lock and just one gear. New models cost Y10,000 (£50)

— All bicycles must be registered with the police for a small fee. They then receive an individual code intended to make recovery easier should they be stolen

— Japanese cities abound with dedicated bicycle parks, usually near railway stations and shopping centres. Japan also boasts some of the world's few multi-storey bicycle parks

— The Bicycle Culture Centerre in Tokyo features a library of bicycle-related books, staff with specialised bicycle knowledge and “a wonderful collection of bicycle character goods from around the world”

Sources: japan-guide.com; Bicycle Culture Centre

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