Who knows. The bike could have been dumped on the street by the murderer and some kids found it and brought it home, not knowing it was related to the murder. I mean, its pretty dumb to keep the bike in the house and dump a body at the curb. After a murder you would think they would want to get rid of evidence, not take it home. One scenario is that it was a stranger abduction and murder and unwitting crime of opportunity for some kids who found an abandoned bike and took it home.
Possible, but at what point do you NOT realize the bike you found is the one plastered all over the County?