Another similar story happened to me.
I was walking my girlfriend home and pushing the bike (little jump bike, valued at £1500). I was jumped beaten up and they ran off with the bike.
Phoned the police, they asked us to drop by at the station (which was a fair bit out for us). Took the details of the incident, but didn't ask anything about the bike itself.
The amusing bit was that the girlfriend knew who the guy was, gave the police their name and address. Yet they didn't' even think to go round until they were made aware that an acquaintance and I were going to pop round for a chat.
Surprisingly the police said that had no evidence it was him that either took the bike of assaulted me and left it like that.
Couple of weeks later I phoned to see what was going on to be told that the case had been closed, which annoyed me greatly. As we knew who it was, where he lived, he's been seen out and about on the bike by several people yet nothing was done and they closed the case without telling me so and letting me wait for them to get in touch.
I found out through my own sources that the bike was stashed away for a while then sold on to someone in the same area.
Anyway, a year later the police get in touch with me and say that they have enough people who were victims of this guy to try and put him away and wanted to know if I would testify in court against him.
Nothing has been heard or done since.