'am I missing something? Why couldn't the police just arrest the scrote on suspicion of theft/robbery? They could then search his property and recover it. I think the response you've had from the police is diabolical. They might be pleasant to you but they will be to the scrote as well, they seem to be doing bugger all to recover your bike when they have more than enough information and reasonable suspicion to do so. The scrotes and chavs seem to be calling the shots, the plod have no influence in this area! It sounds a horrible lawless dive. I think a complaint to the CC or IPCC would be in order. Next time put a tracker in the bike frame.
I would organise a visit to the scrote to introduce him to some of your 'mates'. If you don't get your bike back and it looks like getting out of hand then call plod. You aren't going to get it back if you wait for plod to do something.