Having a bike stolen is quite possibly the worst feeling in the world. There's nothing that makes the heart sink lower than coming back to where you left your bike and seeing the cut ends of your cable lock, the plaintive flap of a forced shed door, or the awful uncertainty of checking all your possessions after a house burglary.
The immediate aftermath is pretty depressing too. You might encounter unsympathetic friends with crystal clear hindsight, unininterested police officers who assume your bike was a £100 Halfords special, or clueless insurance adjusters who can't even pronounce the name of your bike properly. It's tempting to dismiss any chance of seeing your bike again, and with a tiny number of stolen bikes recovered each year, the odds are stacked against you. But if you don't resign yourself to fate and do a bit of leg work, there is a possibility that you might recover your pride and joy.
Make a note of your details
Assuming your bike hasn't been stolen yet, stop reading this website now. Get a pen and paper, and a camera, and go to where your bikes are. Write down every component part from the bar end caps to the inner tubes. Make a note of any damage, like dents, dings or scrapes. Write down the serial number of your frame, and your forks too if they're decent ones. Then take a clear picture of your bike. Put all this information somewhere secure. I keep mine with my passport and birth certificate, which might seem like overkill, but you want to be able to find this stuff when you need it.
Do this now, not later. Now! If your bike gets stolen and you don't have a decent description and pictures, it'll make it that much harder for you to even put in an insurance claim, let alone get it back.
Tell the police, then tell the world
If your bike does get nicked, ferchrissakes tell the people who are in the best position to get back for you. You do hear theft victims complain that the police don't seem interested in stolen bikes but that doesn't mean that there is no point in reporting it. Without a crime report, you won't be able to put in an insurance claim, and if the police do arrest someone riding round on it, there will be no way of proving that your bike is yours.
There's a chance that your bike could turn up in another area, but it might not show as stolen on that particular force's database, so it's also a good idea to register it with Immobilise. This is a free service that lets you record ownership of your bike to a nation-wide database using the serial number (You did take a note of your serial number, didn't you?). The database is searchable by the police (although not the general public). More details here.
Once you've informed the police it is also worth putting the word out in other ways. Let people know via internet forums, mailing lists and this here blog. Some popular mountain biking forums are Singletrackworld, BikeRadar and BikeMagic. If it was a road bike, try Bikeradar's road section, Road.cc, or CTC. If you can, give enough detail to distinguish it from other bikes of the same make and model, and try Googling for your make and model of bike together with the word "stolen" to see if your posts appear.
20th century methods are useful too, such as making up flyers with pictures of your bike and distributing them round bike shops and second hand goods shops. The shop can keep the flyer to hand and check if someone brings in a suspicious bike, much more easily than if the information is stuck on a computer in the back room.
Keep your eyes peeled
You could cruise the streets looking for your bike, but it's a bit of a long shot. A better option is to check out local second hand shops - most second hand bike shops will be able to spot a stolen bike a mile off, and refuse to buy it, but it may turn up in a pawn shop like Cash Converters . Talk to the shop and leave them a picture of the bike as they will be able to recognise it if it comes in. Some shops keep goods for 28 days before putting them on sale.
There's also a fair chance that your stolen bike will pop up somewhere on the internet. The relative anonymity and low cost of websites like Gumtree, Trade It, Preloved and eBay means that they are a gift to fences. That said, they are also a gift to the police, who will normally be able to get an advertiser's details from the website if they have cause to think a sale is suspicious. Check the above sites to see if your bike pops up on one of them. You can do this manually, but if you prefer you can set a Google Alert (e.g. "For sale Bristol Specialized Stumpjumper"), a live RSS feed of Gumtree search results, and an eBay saved search.
These will automatically notify you when an advert matching your chosen description is posted. The eBay function is very good - you even get a little picture of the item so you can see instantly if it's yours or not. Results with Google can be a bit mixed, but the speed of the alerts is getting quicker, and given how easy it is to set up it's worth doing.
Getting it back
If you spot your stolen bike out and about or on the web, inform the police. It might be tempting to take matters into your own hands at this point, but realistically the police are the people to get in touch with, not your wannabe hardman mates. Make a note of the contact you speak to at the police and update them if you receive any more information. If they recover your bike, they may need to hang on to it to use as evidence and you may also need to give a statement.