Whether it's bicycles, cars or houses, if thieves really want to get past the lock on something, they can. The trick is to simply not make it worth their while to do so, by adding extra hassles. The Stemlock is just such a hassle. It internally disconnects a bike's handlebar stem from its fork, making it impossible for a thief to steer.
For regular riding, obviously, the stem and fork stay securely connected. Upon parking the bike, users insert the included key in the top of the Stemlock, push it down and twist it a quarter turn, then remove it. The stem is then disconnected from the fork, resulting in the handlebars swinging left and right with no effect on the angle of the front wheel.
Not only does this make the bike a much less appealing target, but it also allows for easier parking in cramped spaces such as hallways, as the handlebars can be turned sideways without also turning the front wheel.
The Stemlock is made by IXOW, the same French company that is bringing us the Synchrobox. A rep tells us that both products are scheduled to launch in August at the Eurobike show, with the Stemlock priced at €74.90 (about US$103).
Pricing for a similar existing product, the n'lock, starts at 112 Swiss francs ($126). The Flipphandle also lets you turn your bars sideways for storage and transport, but it doesn't incorporate a lock.