Aww, damn, coulda sworn it was our fair city, Cambridge, MA. Shoulda known by the "nicked" and the "mum". If you woulda said "me mum" instead of "my mum" I'd have nailed it for sure

Or maybe mentioned the colour of your bike or something like that.

Still, I dunno if you can score a bike for £40 or so at a rummage sale, I'd jump on it and ride that for commutes if you have a killer MTB you don't want nicked.