In a parking lot near the East River in Manhattan, Adriana Alltari gathers her courage, lifts her feet off the ground and wobbles away on New York's latest mode of public transport: a bicycle.

Alltari, a 32-year-old engineer, was taking part in free bike riding classes as the Big Apple makes final preparations for a program that will revolutionize a city known more for traffic jams of yellow cabs and other vehicles of the four-wheeled variety.

On May 27, thousands of blue "Citi Bikes," named after their sponsor CitiBank, will appear in high-tech stations around the city in a sharing program modeled on successful projects in Paris and other cities around the world.

For Alltari, who got turned off cycling by a series of crashes when she was eight years old, the road to bicycle heaven is shaky. Taking her lesson against a backdrop of the Brooklyn Bridge, she zigzagged, but found herself steadily improving.

The class of about 20 adults, mostly women, was busy ahead of the roll-out for Mayor Michael Bloomberg's twice-postponed project. Alltari said classes were booked solid in March and April.

"It is scary, but fun," she said. "I fell so many times when I was a kid, I decided I will never ever get on a bike. But here I am."

City officials said Thursday the launch date will be the big Memorial Day holiday on May 27. However, at first, only annual pass holders will get to ride, while everyone else, including those looking for the free quick rides, joins in on June 2.

Already, nearly 300 stations have been installed and more than 8,000 people have paid the approximately $100 rider's annual fee.

Initially, New York will get some 6,000 bicycles. The target is 10,000 spread across 600 stations, which will leave only China's Hangzhou, with 60,000 bicycles, and Paris with 20,000 "velibs," boasting more.

The New York program will give cyclists free-of-charge rides lasting up to 45 minutes, but make them pay for any more, with daily and weekly tickets on offer, as well as the annual passes.

After trying a demonstration model of one of the blue bikes, David Dartley, a 38-year-old artist, was sold on the idea.

"I expect to ride them a lot to go to meetings in the middle of the day to go to other offices. It will be better than the subway or a taxi, or walking," he said.

"I'll be able to go to a bar and have some drinks at night and I won't have to worry about biking myself home after: I can leave the bike."

New York has gradually come to embrace the bicycle under health-conscious Bloomberg. But the crowded and sometimes traffic-clogged streets are often considered a hazardous environment for the cyclist.

Dartley said he wasn't worried. "Once these bikes are on the streets, drivers are going to calm down and I think everyone is going to be safer," he said.

Elizabeth Haddad, a 26-year old writer, said "biking in New York is scary and can be dangerous."

But with a helmet, "it is a really good option," she said of the Citi Bike effort. "I've done it in France. They're great."

So far, the New York bikes have only one thing missing, Haddad said: "the basket."