In many cases yes. African American kids are told by their friends that you should only certain sports. I never got any strange looks from my friends when I played basketball, I got a few when I started playing tennis, and was told I was strange because I started rollerblading and cycling.

As a kid you see the big money sports are football and basketball, and its those athletes the kids emulate. I would guess that if you are seeing african americans on bikes, they are young kids or adults who could care less what their friends say.

Just my .02