Motorcycles are fundamentally more vulnerable to theft than most other forms of transport, but they need not be. The use of a good lock will protect a motorcycle against most forms of attack and reduce the theft rate dramatically. Incredibly, motorcycle security experts still believe that well over half of all motorcyclists use no form of physical security other than the steering lock, which itself offers very little resistance to a determined attack. Furthermore, just like an alarm or an immobiliser, the steering lock does not prevent thieves from simply lifting the motorcycle into the back of a van and transporting it to a garage where they can re-mobilise the bike at their leisure. These figures are supported by recent research carried out by Oxford Products USA into the amount of bikes stolen within America each year. In 2011 every 11 minutes seen a motorcycle being stolen according to NICB's 2011 ForeCAST.
The best advice is simple: Lock it, or lose it!