It was after dark when Kieu Tran slid the bright blue bike into a bright blue dock in Point Breeze.

Her commute was almost over. The docks, part of the city's bike-share program, Indego, are a short walk from home, where her four children waited to eat dinner. Since Indego's April debut, Tran, 45, has discovered that the 15-minute bicycle trip to her job at Peirce College's admissions office in Center City takes half the time as riding the bus and is cheaper.

"I'm going to try to go through the winter," she said.

The city would love more bike riders like Tran, who lives in a neighborhood with a median household income of about $30,000. Yet an analysis of rider data from April to September shows that Indego has struggled with one of its founding missions: to get riders from low-income areas up on two wheels.

Bike share offers publicly owned cycles for rent at 73 stations in the city. The program has sold 8,300 memberships since April and reported 421,000 rides taken. Indego has become a reliable commuting option for thousands of Philadelphians.

But The Inquirer's analysis of April-to-September rider data shows that the five least-used bike-rental stations in the city were in neighborhoods with median household incomes below $25,000.

The least-used rental station, at 11th and Poplar Streets, saw 71 bikes signed out in September. That's about the same traffic that the kiosk in Rittenhouse Square, the city's most popular, gets in 12 hours.

A Philadelphia neighborhood with one of the lowest median household incomes, Mantua, has two Indego rental stations. Both are among the least used, the data show. One near 39th and Mount Vernon Streets reported 461 rentals in six months. The other, at 36th and Spring Garden Streets, at the fringe of Drexel University's campus, reported 565 rentals.

Promoting biking means changing people's habit of using public transit or cars, said James Wright, a manager at the community-development organization People's Emergency Center, based in Mantua.

"Right now, it's not really on their radar," he said of bike shares. "I don't really know if they paid attention to it, to be honest."

With membership at $15 a month for unlimited one-hour rides, Indego offers a cheaper, healthier way to commute than bus or subway. It also offers freedom, Wright said, from the set routes used by public transportation.

Despite those benefits, Indego's challenges reaching the city's lower-income residents are neither surprising nor unique.

An April 2015 study from the National Association of City Transportation Officials stated that "while bike share offers clear financial benefits, low- income people are not proportionally represented among U.S. bike share users."

Indego is entering its second phase this year, with 24 new stations planned, some likely to go to poorer neighborhoods. Philadelphia officials overseeing the program will spend the winter analyzing data and reaching out to riders, to determine how to sell bike share's advantages to people feeling financial pressure.

"Our goal is to learn from each station," said Aaron Ritz, complete streets implementation manager in the city managing director's office of transportation and infrastructure. "We're using this ongoing learning process to drive the next round of station planning."

Indego's outreach efforts have included organized rides, an ambassador program that used neighborhood activists to promote the benefits of biking, and outreach to such community leaders as Wright.

The program's fare structure is one of its most significant innovations. A monthly membership payment plan helps attract people put off by a pricey initial investment. It also allows people to pay with cash, an entry point for those without debit or credit cards.

Of the program's 8,300 members, the number paying with cash is in the double digits, city officials have said.

Getting communities to buy in also has proved a challenge. In Point Breeze, two businesses, a 7-Eleven and a Family Dollar, are registered to process cash payments, according to Indego's website (www.rideindego.com). But store clerks asked about Indego cash payments said the businesses did not process them.

In an actual cash transaction for Indego, a clerk would simply need to scan a bar code that a rider receives online, Ritz said. Still, he said, having staff at the businesses who were so uninformed was a problem. "We're looking to update the cash membership program," he said.

It's too soon to draw conclusions from the data, said Ritz, but he noted that density and geography are two factors that might make bike-share stations in poorer neighborhoods less used.

Stations in densely populated areas with diverse development tend to do better, he said. Poorer neighborhoods tend to have lower residential density.

To give it the best chance of reaching a lot of people, Indego's original stations were clustered in Center City and University City, where there are offices, cultural attractions, and lots of residents. A neighborhood like Point Breeze or Mantua is on the network's outskirts, with fewer directions a cyclist can go to reach another station.

Adding stations outside the city's core will be in the mix during this year's expansion, officials said.

Boston's bike share, Hubway, was founded five years ago and has had some success getting low-income residents biking.

Hubway, which also serves neighboring Somerville, Brookline, and Cambridge, Mass., has more than 4,000 members in Boston, about 15 percent of them low-income residents. Its membership is $85 a year, but those whose income and family size meet the program's measures of low income can get annual memberships for just $5.

Indego will likely keep its $15 membership for most users, Ritz said, but it is considering creating a greater spectrum of prices.

"We're beginning the stages of piloting projects where we target groups with different offers and different prices to encourage ridership and to lower any financial barriers," he said.

Hubway staffers are regulars at community meetings and keep up a presence in Boston neighborhoods, but they say what helps most is word-of-mouth and visibility.

"That's part of the best marketing, having the bikes out there," said Najah Shakir, program manager at Boston Bikes, which oversees Hubway for Boston.

Wright, the Mantua community leader, said Indego's staff could be even more visible in the neighborhood by attending meetings that draw crowds of residents invested in the community.

"It just takes time and effort and massive outreach because you're changing the culture," he said. "People are used to SEPTA or driving" or taking cabs.

This year, Indego will begin a major marketing push, officials said. It will seek customer feedback and conduct surveys.

The system will work best if it responds to the needs of riders, Ritz said: "Part of that learning is making sure we're aware of trips people need or want."

Even where ridership is low, there are signs that Indego is catching on. At the station at 39th and Mount Vernon Streets and the one in Point Breeze where Tran starts her commute, the data show rider use grew during peak summer.

Tran is an Indego convert, she said, and surprised her friends by saying that, even on cold days, biking is better.

"If I took the bus, I would have to stand and wait and then get on the second bus," she said. "On this, I was always moving."

jlaughlin@phillynews.com

215-854-4587

@jasmlaughlin