As always, setting is comprised of two elements: place and time. Both are significant in Bambara's young adult novel Raymond's Run.
The setting of place is New York City and, specifically, the community of Harlem. (Bambara grew up there as well.) In fact, the community of Harlem is spoken of even more specifically as actual street names that comprise many of the scenes. Raymond's actual "run" is on Amsterdam Avenue! However, other streets set other scenes such as Broadway, 34th street, etc. The setting of place presents an atmosphere of survival as Squeaky needs to protect both herself and her brother.
In regard to the setting of time, it's important to realize that this was a "current" story in the time it was written. It was first published in a collection of short stories in 1971 called Tales and Stories for Black Folks. Considering the date of publication and that the story is modern, we can safely assume that the setting of time is "recent" which would involve both the civil rights movement and the "Black Power" movement in the 1960s and 1970s. Specifically, this timing augments the strengths (as opposed to the weaknesses) of a community being strictly African American.
Even though the following quote is by the author, but not in the context of the story, it is the perfect way to characterize the setting of Raymond's Run:
I work to tell the truth about people’s lives; I work to celebrate struggle, to applaud the tradition of struggle in our community, to bring to center stage all those characters, just ordinary folks on the block . . . characters we thought we had to ignore because they weren’t pimp-flashy or hustler-slick or because they didn’t fit easily into previously acceptable modes or stock types.