Most of the pupils who spill out at home time from the andr malraux french school in hanwell, west london, are shepherded by their parents to waiting cars. but this term, when melinda marchal picks up her children, shes often waiting with something different.

On these days, her daughters, seven-year-old charlotte and lodie, age five, emerge from school pushing their little bicycles. marchal hoists their two-year-old brother, hugo, into a child seat over the back wheel of her own bike. she then unfolds a device called a followme tandem that securely attaches lodies bicycle to the rear of her own. charlotte prepares to ride alongside.

The marchals are part of a growing trend of families in london and other urban centres using bicycles including electric bikes and additional bike seating to make at least some of their regular journeys. this comes about as more people look to avoid car congestion or social contact on public transport.

The new demand has led to an international shortage of bicycles and components, with many models out of stock.

Alix stredwick, founding director of carryme bikes, a north-east london retailer that specialises in family cycling, says demand has tripled or possibly quadrupled this year compared with last.

Some families are concerned they might contract coronavirus on public transport, stredwick says, while others are simply recognising that bikes can outperform cars in cities like london, where the average speed of road traffic hovers around seven or eight miles an hour.

Her account chimes with my own experience. eschewing advice that parenthood meant buying a car, my wife and i transported our own children, now 13 and 19, by bike from a young age.

Theres more and more families thinking its not worth it, stredwick says of owning of car. you cant park it anywhere its just a burden.

Marchal, a full-time carer on a career break from a job in accountancy, ascribes her shift from car usage partly to environmental concerns. she says she also wants to avoid the hassles of new strictures introduced in back streets in her area, aimed at creating low-traffic neighbourhoods and that force traffic to keep to main roads.

Weve been trying to do our part, she says on the environmental question, but i still always had this niggle that i would rather cycle than have another car on the road.

Nevertheless, as marchal strains to haul two children up a sharp slope near the school, it is clear that the approach she and many others have adopted can present challenges. one is finding an appropriate machine.

Its almost like [choosing] shoes, says roman magula, managing director of london green cycles, a specialist retailer. there are different kinds for different activities, all with their own (dis)advantages.

The critical decision for many families is whether to invest in a cargo bike (where children sit in a box in front of the parent) or to adapt a conventional bike, as marchal does.

Adaptations, in general, cost no more than a few hundred pounds, while a four-child cargo bike may cost up to 4,000. conventional bikes can be adapted by adding a seat to a luggage rack or cross bar, hitching on a buggy-like trailer or adding a single-wheel trailer bike to a parents bicycle.

With two children six years apart, this is the approach my wife and i took. we initially attached a seat to one of our bicycles to transport our daughter, and replaced it with a trailer bike when she was old enough. our son either travelled in a seat or a child-carrying trailer, before graduating to the trailer bike when his sister was able to ride on her own.

We found that the trailer worked best because of its low centre of gravity, but as our son grew it became easier to have him on the trailer bike until he was big enough to ride on his own.

Users of cargo bikes say they offer big advantages. the low carrying position reduces the balance problems inherent in rack-mounted seats, and they are generally easier to use than sometimes complicated equipment like the followme tandem.

Many cargo bikes now use battery or motor technology for electric assistance which can double the price of the bicycle. magula says modern designs are light and manoeuvrable enough so that often only muscle power is required, but electric assistance has transformed their potential.

Theyve become so much more accessible and very usable, which means that people who before couldnt, now find its realistic for them to use a bike to get to work, he says.

Ruth-anna macqueen, a junior doctor and founder of the family cycling uk facebook group, says her first child travelled on a luggage-rack mounted child seat. however, a complicated school and nursery run with a steep hill to tackle prompted the family, whose children are now nine, seven and three years old, to invest in a babboe city cargo bike with electric assistance.

I think the only regret of most people who have ended up with cargo bikes would be not buying one straight away when we started having children, macqueen says.

Stredwick says many parents generally feel that cargo bikes keep children safer than other bicycle arrangements, and would not use them unless they felt safe. (there are no uk statistics separating incidents involving cargo bikes or bikes carrying children from wider casualty statistics.)

The parents we deal with have made the decision that it makes more sense to be using these machines than taking their children around by car, she says.

Marchal, meanwhile, enjoys much of the journey between school and home along back streets and traffic-free paths. she chats to both girls and quizzes charlotte on her understanding of the road markings. she acknowledges that the family may rethink the decision to forego a cargo bike.

But she contrasts the cycling trip favourably with the experience of taking the children by car. every trip we make is a learning experience, she says.

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