If you use a U-lock like this...
If you use a U-lock like this Abus, keep it away from the ground, which a thief can use to get extra leverage against it.
Just because no one has ever stolen your motorcycle before, that doesn't mean that it won't happen today. All kinds of motorcycles get stolen from all sorts of places. Though popular bikes, especially those that are frequently crashed or have expensiove crash-susceptible parts are the most common targets, even boring little beaters can get snatched. We have heard of old beat-up "entry-level" being stolen despite being carefully locked up and covered as well brand new bikes wearing locks and stashed away in seemingly safe locked private garages inside gated yards. Motorcycle gathering places—shows, races, rallies, charity ride, etc. are often targeted. Urban areas are probably more dangerous for motorcycles, but we have also heard of bikes being stolen from farm sheds.
They can be stolen on impulse by joy riders, by real thieves because they were easy targets, or by full-fledged gone-in-60-seconds professional thieves because that have customers for them. You may have trouble fending off the latter group once they have spotted your bike, but you can more effectively defend agains the first two types.
1. Lead Them Not Into Temptation.
The less your bike is seen, the less likely a thief will cozy up to it. If you don't have a garage, keep it covered. Not knowing what's underneath makes it harder to assess the difficulty of stealing it ot to know if it's even a bike they want. By putting a BMW cover on your Harley, you can also create the impression that it is a bike that is less likely to be stolen than what it actually is.
2. Steer Clear
Although readily defeated, your bike's steering lock can be a first-step defense and will discourage easy maneuvering of the bike. It is even more useful if your ignition and steering locks are separate, so the thief needs to defeat two locks to escape with your scooter.
3. Keep It Up
Whatever lock you use, don't rest it on the ground, where the thief is more likely to be able to get enough leverage to break it. If you attach to lock up away from the groud, the thief probably won't that extra leverage to pry the lock. The lock should be attached through the frame, or less desirably, forks or wheel.
4. Lock It Down
A disc lock might inconvenience joy-riders, but determined thieves can simply hoist such a bike into a waiting truck. If you add a cable to it and anchor that to something solid, you have a more formidable. Even bikes inside garages should be securely locked.
5. The Power Of Two
It's best to use two or more locks of different types in addition to your bike's built-in lock(s). Unless a thief has surveiled your bike, he probably won't be prepared to tackle different kinds of locks. And if one of them anchors the bike to something immovable, a gang won't be able to carry it to a truck.
Theft increases during the...
Theft increases during the riding months, when bikes are more likely to be parked some place vulnerable and in demand.
6. Don't Cheap Out
Go for the good stuff when shopping for security: Alarmed disc locks, U-locks of hardened steel and asymmetrical chains (5/8 inches or greater) all rate highly.
7. Get Sneaky
If you're really determined to foil the bad guys, wire up a kill-switch or spring-loaded switch that must be held down when the start button is depressed. Some riders have foiled attempted thefts by simply removing the main fuse when they parked their bikes.
8. So That's The Key!
Make a record of your key numbers, then file them off the locks if they're stamped on. Anyone with a number can have a key cut to fit.
9. Shine A Light
If you park outside, choose a well-lit, conspicuous area. If you can't lock your bike to something solid and stationary, try another bike (preferably not one belonging to a stranger). Even plastering your bike with "Alarm Installed" stickers could discourage the bastards.
10. Make Some Noise
Alarms may seem like a good way to attract attention to the fact that someone is attempting to purloin your bike, but in most places we have gotten so used to false alarms that people don't investigate or even bother to look. But everyone pays attention to sounds of destruction—such as breaking glass. A large stack of beer bottles with a trip wire makes a sound that everyone will investigate when it gets tipped over.
11. Watch Your Back
Professional thieves often find the bikes they want to steal (probably because they have orders for them) by following them to where they are parked during the day or night. Then they size up the situation and come back with what they need to bag the motorcycle. So, as you approach your destination, especially if it's home, watch your mirrors for several blocks. If someone seems to be following you, try to lose them, pull over and let them pass (leaving an escape route in case they are bikejackers), make a U-turn or go around the block. Anyone who continues to follow you is probably trouble. Just don't go home or into your company or school parking lot until you have shaken them off.