PARIS » Just as Le Corbusier's white cruciform towers once excited visions of the industrial-age city of the future, so Velib', Paris' bicycle rental system, inspired a new urban ethos for the era of climate change.

Residents here can rent a sturdy bicycle from hundreds of public stations and pedal to their destinations, an inexpensive, healthy and low-carbon alternative to hopping in a car or bus.

But this latest French utopia has met a prosaic reality: Many of the specially designed bikes, which cost $3,500 each, are showing up on black markets in Eastern Europe and northern Africa. Many others are being spirited away for urban joy rides, then ditched by roadsides, their wheels bent and tires stripped.

With 80 percent of the initial 20,600 bicycles stolen or damaged, the program's organizers have had to hire several hundred people just to fix them. And along with the dent in the city-subsidized budget has been a blow to the Parisian psyche.

“;The symbol of a fixed-up, eco-friendly city has become a new source for criminality,”; Le Monde mourned in an editorial over the summer. “;The Velib' was aimed at civilizing city travel. It has increased incivilities.”;

The heavy, sandy-bronze Velib' bicycles are seen as an accoutrement of the “;bobos,”; or “;bourgeois-bohemes,”; the trendy urban middle class, and they stir resentment and covetousness. They are often being vandalized in a socially divided Paris by resentful, angry or anarchic youth, the police and sociologists say.

Bruno Marzloff, a sociologist who specializes in transportation, said, “;One must relate this to other incivilities, and especially the burning of cars,”; referring to gangs of immigrant youths burning cars during riots in the suburbs in 2005.

He said he believed there was social revolt behind Velib' vandalism, especially for suburban residents, many of them poor immigrants who feel excluded from the glamorous side of Paris.

“;It is an outcry, a form of rebellion; this violence is not gratuitous,”; Marzloff said. “;There is an element of negligence that means, 'We don't have the right to mobility like other people, to get to Paris it's a huge pain, we don't have cars, and when we do, it's too expensive and too far.”;'

Used mainly for commuting in the urban core of the city, the Velib' program is by many measures a success. After swiping a credit card for a deposit at an electronic docking station, a rider pays one euro per day, or 29 euros (about $43) for an annual pass, for unlimited access to the bikes for 30 minute periods that can be extended for a small fee.

Daily use averages 50,000 to 150,000 trips, depending on the season, and the bicycles have proven a hit with tourists, who help power the local economy.

But the extra-solid construction and electronic docks mean the bikes, made in Hungary, are expensive, and not everyone shares the spirit of joint public property promoted by Paris' Socialist mayor, Bertrand Delanoe.

“;We miscalculated the damage and the theft,”; said Albert Asseraf, director of strategy, research and marketing at JCDecaux, the outdoor-advertising company that is a major financer and organizer of the project. “;But we had no reference point in the world for this kind of initiative.”;

At least 8,000 bikes have been stolen and 8,000 damaged so badly that they had to be replaced—nearly 80 percent of the initial stock, Asseraf said.

JCDecaux must repair some 1,500 bicycles a day. The company maintains 10 repair shops and a workshop on a boat that moves up and down the Seine.

JCDecaux reinforced the bicycles' chains and baskets and added better theft protection, strengthening the mechanisms that attach them to the electronic parking docks, since an incompletely secured bike is much easier to steal. But the damage and theft continued.

“;We made the bike stronger, ran ad campaigns against vandalism and tried to better inform people on the Web,”; Asseraf said. But “;the real solution is just individual respect.”;

Between 2007 and 2008, the number of infractions related to Velib' vandalism rose 54 percent, according to the Paris police.

“;We found many stolen Velib's in Paris' troubled neighborhoods,”; said Marie Lajus, a spokeswoman for the police. “;It's not profit-making delinquency, but rather young boys, especially from the suburbs, consider the Velib' an object that has no value.”;

Sometimes the bikes are also victims of good old adolescent anarchic fun. These attitudes are expressed by the “;freeriders,”; and a bicycle forum, where a mock poll asks riders whether the Velib' can do wheelies, go down stairs and make decent skid marks.

It is commonplace now to see the bikes at docking stations in Paris with flat tires, punctured wheels or missing baskets. Some Velib's have been found hanging from lampposts, dumped in the Seine, used on the streets of Bucharest or resting in shipping containers on their way to North Africa. Some are simply appropriated and repainted.

Finding a decent one is now something of an urban treasure hunt. Geraldine Bernard, 31, of Paris rides a Velib' to work every day but admits having difficulties lately finding functioning bikes. “;It's a very clever initiative to improve people's lives, but it's not a complete success,”; she said.

“;For a regular user like me, it generates a lot of frustration,”; she said. “;It's a reflection of the violence of our society and it's outrageous: the Velib' is a public good but there is no civic feeling related to it.”;

Still, with more than 63 million rentals since the program was begun in mid-2007, the Velib' is an established part of Parisian life, and the program has been extended to provide 4,000 Velib's in 29 towns on the city's edges.

So despite the increasing costs, Paris and JCDecaux are pressing on. The company invested about $140 million to set up the system and provides a yearly fee of about $5.5 million to Paris, which also gets rental fees for the bikes. In return, the company's 10-year contract allows it to put up 1,628 billboards that it can rent.

Although JCDecaux will not discuss money figures, the expected date for profitability has been set back. But the City of Paris has agreed to pay JCDecaux about $600 for each stolen or irreparably damaged bike if the number exceeds 4 percent of the fleet, which it clearly does.

In an unsuccessful effort to stop vandalism, Paris began an advertising campaign this summer. Posters showed a cartoon Velib' being roughed up by a thug. The caption read: “;It's easy to beat up a Velib', it can't defend itself. Velib' belongs to you, protect it!”;