This is Street Wars, a weekly series on the battle for space on New York’s streets and sidewalks.

On a chilly Saturday evening in April, Kevin Daloia took a bicycle that he had painted white and locked it to a pole on East 161st Street and Melrose Avenue in the Bronx. Then he climbed up, stood on the seat of the bike and mounted a metal sign on the pole above it.

“Cyclist Killed Here/Rest In Peace,” the sign said.

The cyclist, Thierno Balde, was hit by a car on Feb. 23 while on his way home from prayers at his mosque. The driver fled after the crash and then ditched a crumpled Jeep Grand Cherokee a few blocks away, according to reports.

The police said Balde had run a red light. But the authorities also said the driver had been speeding.

Daloia didn’t know Balde, but that didn’t matter.

In his free time, Daloia volunteers to paint old bicycles and fasten them to poles as “ghost bikes” for the New York City Street Memorial Project, which consists of installations around the city marking locations where cyclists have died.

The bikes — completely white, including tires, spokes and pedals — serve as stark memorials, both an alert to passers-by that a cyclist was killed and a reminder of the dangerous conditions cyclists face in New York. The activists who install the bikes hope to catch the attention of drivers as well.