Los Angeles Mayor Antonio Villaraigosa will unveil a $16-million bike-share program Sunday that aims to put thousands of bicycles at hundreds of rental kiosks across the city.

Initial plans are to add 400 stations and 4,000 bicycles over the next 18 to 24 months in areas around downtown Los Angeles, Hollywood, Playa del Rey, Westwood and Venice Beach.

The private investment from Bike Nation will not need any city money, according to the mayor’s office and the company. Bike Nation has agreed to a minimum contract of 10 years.

“In tough economic times like these, we knew it wasn’t feasible to start a public bike-share program. But we do know it’s what L.A. needs,” Villaraigosa said.

“We’re building the infrastructure, we’re making it safe, and we’re making it practical for Angelenos to get from point A to point B on two wheels,” he said.

The mayor is scheduled to make the announcement at CicLAvia, which has become L.A.'s recurring marquee event for bicyclists and pedestrians. An estimated 100,000 people are expected to participate in the event, which is intended to promote individual health and the environment and will cover 10 miles of car-free streets in downtown Los Angeles and beyond.

“This is exactly what L.A. needs,” CicLAvia organizer Aaron Paley said. “If you take the bus, or you take the train, or you’re walking out of your house and you need to get somewhere, how do you accomplish that short trip in between? Bike share is definitely the way to do it.”

There are similar bike-share programs in Washington, D.C., and Denver as well as many European cities.

A smaller bike-share program will open in Anaheim in June, according to Bike Nation. Company officials said that they would work with L.A.'s Transportation Department to finalize areas to put the kiosks and that they hope the program will eventually grow beyond 4,000 bicycles.

Would-be cyclists in L.A. will be able to rent bikes; prices include $6 for the day, $1.50 for an hour or $4.50 for 90 minutes. Trips shorter than 30 minutes will be free; one-year passes will run $75.

The bicycles are made without a chain and have special tires to reduce the possibility that they will get a flat or break down during their trip. Riders will need to bring their own helmets.

There is also GPS technology on the bicycles — partly a counter-theft measure — so they can be easily located. Riders also can use mobile applications to find their routes and other kiosks.

Alexis Lantz of the Los Angeles County Bicycle Coalition said that the program is a big step forward but that it’s still only a step toward making the city a bike haven.

“We think bike sharing can really bring a lot to the city and greatly increase the number of people who use bicycles, especially for short trips, and introduce both Angelenos and tourists to how easy it is to bike around,” Lantz said.

But “in order for bike sharing to thrive, we need to have a connected network of streets where everybody can feel safe and comfortable bicycling as well as provide clear way-finding signage,” Lantz said.

ari.bloomekatz@latimes.com