Washington, DC (CNN Business) Lyft is returning e-bikes to its San Francisco Bay Area fleet just days after it filed a lawsuit to block competitors from launching their own e-bikes in the city.

pulled its e-bikes off the streets of San Francisco, New York and Washington, DC, in April following a spree of crashes in which riders were thrown over the handlebars when the front brake applied too much pressure, freezing the wheel in place.

The new e-bikes have a different braking system on the front wheel, using a disc brake instead of a roller brake. Following the crashes , Shimano, the manufacturer of the roller brake, said Lyft hadn't included a component to prevent excessive braking.

Lyft's new e-bikes will first appear in San Jose on Tuesday, and then San Francisco and East Bay later this month, according to Lyft. The company said it will roll out hundreds of e-bikes each month. E-bikes will return to New York and Washington, DC, this fall.

Lyft's entry into the bike and scooter market has been turbulent since first announcing plans to acquire bikeshare company Motivate in July 2018. The acquisition wasn't officially closed until December. Lyft has had to rush to keep up with competitors who have raised more than $1 billion and were first to launch e-bikes and e-scooters nationwide. In April, Lyft pulled all of its electric bikes after riders were injured. Its top executive for bikes and scooters left the company this spring, after less than a year on the job.

On Friday, Lyft sued San Francisco, arguing its new stationless bikeshare program violates the city's contract with Lyft. San Francisco announced in late May plans to expand its pilot of dockless, electric bikes, which would allow thousands of bikes from Lyft's competitors into the city.

"We need San Francisco to honor its contractual commitments to this regional program — not change the rules in the middle of the game," Lyft said in a statement.

The two sides disagree over whether the 10-year contract signed in 2015 applies to dockless bicycles, which do not need to be parked at a docking station. Early bikeshare systems, such as those Motivate operates in major US cities, rely on docks. Newcomers, such as Uber's Jump brand , operate bicycles that can be locked to bike racks or sign posts on streets.

"Lyft can seek a permit for dockless bikes on equal footing with everyone else," a spokesman for city attorney Dennis Herrera said in a statement. "[The agreement] does not give Lyft the right to a monopoly on bike sharing in San Francisco."

Lyft argues a precedent was established when the bikeshare company Bluegogo wanted to launch in San Francisco in 2017, and the city warned Bluegogo that the exclusive right to operate had been granted.

Lyft's lawsuit also accuses Uber and Jump of lobbying San Francisco officials to give it an exemption to Lyft's exclusive deal with the city. Uber declined to comment.

The rivals, both of which recently went public, are increasingly fighting each other for the right to operate bikes in cities. Earlier this year, Lyft was awarded an exclusive contract in Chicago following objections from Uber — which launched a public relations campaign, "Pump the Brakes, Chicago."

The companies appear motivated by the popularity of e-bikes, and their potential to disrupt the ridehailing business.

Uber reported in its S-1 that 21% of its trips are less than a mile, and 46% are under three miles, the kind of distances e-bikes could serve well. Uber said in 2018 that new Jump riders in San Francisco were more likely to continue taking the e-bikes than one of its ridehail vehicles.

Lyft is redocorating bikes in San Francisco that used to carry the Ford GoBike name as the system is being renamed Bay Wheels.

Lyft found this year that its e-bikes were being used three times as frequently as its traditional pedal bikes. Riders also take longer trips on the e-bikes.

Lyft has broken its daily bikeshare ridership record in New York City twice in the last month since allowing riders to book a single bike ride on CitiBike through the Lyft app.

Jump is operating in San Francisco under the city's 18-month pilot for electric, dockless bikes, which ends this month. Motivate didn't have an e-bike ready when the pilot was first developed. The city says demand is high, and that it wants to add thousands more shared bikes to the city. Motivate and Lyft say they're ready to deploy 7,200 e-bikes in the next year.