Stolen Bikes UK provides a number of services to help you recover your bike if stolen:
Find that Bike: https://findthatbike.co.uk/ pulls together adverts for second-hand bikes from various websites, including Gumtree and eBay, into one large search able gallery. You can also set up an email alert to inform you if a bike matching your search is listed for sale.
Check that Bike: https://checkthatbike.co.uk/ collates information from insurers, bike manufacturers and the Police about recovered stolen bikes, and allows members of the public to check their bike frame number against the records held on the database.
Please report information on bike crime by calling 101, or if a bike crime is in progress call 999.