A lock assembly includes a lock cylinder, for actuating a latch assembly, including a lock sleeve, first and second lock rotors, having first and second keyways respectively, rototably fitted in the lock sleeve, and a plurality of tumblers for locking up the first and second lock rotors. A key includes a key head having predetermined locking serrations arranged in such a manner that when the key head is inserted into the first keyway, the locking serrations are adapted to unlock the first lock rotor and enable the first lock rotor freely rotating until the first keyway is aligned with the second keyway, simultaneously, the key head being adapted to insert into the second keyway such that the locking serrations are adapted to unlock the second lock rotor to enable the second lock rotor to freely rotate to control the locking and unlocking of the latch assembly.

To provide a key cylinder device equipped with a handle lock mechanism which can maintain a handle lock mechanism of a key cylinder unit with a shutter to provide an improved assembleability of the key cylinder device. The bolts for fixing a shutter housing are attached from the back surface of the top plate of an inverted angular U-shaped bracket. Thus, even when a gap is generated between the shutter housing and a vehicle body cover, the bolts are not exposed and hence cannot be easily loosened. In addition, by mounting the key cylinder device in the vehicle body cover and then mounting the vehicle body cover thereon, assembleability can be improved.

A helmet can be secured using a front fork lock by placing an end of the motorcycle's handlebars through the helmet and then locking the handlebars. In some configurations a sturdy protrusion, such as metal, graphite, etc., is affixed to an end of the handlebars or to a part of the motorcycle frame to make removal of the helmet in the locked position impossible, or very difficult. Different embodiments disclose a protrusion attached to an end of a hand grip, to a swing point on a handlebar, or some other portion of a handlebar. Protrusions can also be affixed to the motorcycle frame. Protrusions can be made to swing out for securing a helmet and to swing flush with the motorcycle frame to prevent unwanted encumbrance to a rider. Other embodiments disclose protective ways to attach the protrusions so that they cannot be easily removed.

A motorcycle having a fork lock includes a cover which is adapted to be manually moved between a cover position where the cover overlies the fork lock and an uncovered position where the fork lock is exposed to allow a key to be inserted into the fork lock. The fork lock is attached to a mounting member carried between a pair of handle bars for the motorcycle. This mounting member includes a raised platform of a predetermined configuration in which the fork lock is seated. The cover includes a cover plate and a base plate, and the base plate has an underside to which is secured a double sided adhesive member. A first side of the adhesive member is bonded to the underside of the base plate and the second side of the adhesive member having an adhesive surface. The base plate includes a recess portion having a configuration substantially the same as the predetermined configuration of the raised platform, so that the base plate fits snugly over the platform and the planar surface contacts the second side of the adhesive member to bond this second side to the planar surface.