There are three outstanding suppliers of bike locks: Abus (in Europe), Magnum/OnGuard, and Krytonite. If you review the locks that have earned "gold" ratings at SoldSecure, you will see that the majority of "gold" rated locks are supplied by these companies.
If you purchase an OnGuard/Magnum lock from an AUTHORIZED dealer in Germany, you will receive warranty papers that includes the phone number and address of the company that obligated to provide warranty service. Contact THAT company, and you will get help. Contact someone who is NOT authorized to provide warranty service in Germany, and they (strangely enough) are unlikely to assist you.
It is pretty simple. In any nation around the world, when you buy a bike lock, buy from an authorized dealer, not some internet discount fly-by-night. And, when the lock needs service, contact ONLY the specific company contracted to provide warranty service in that particular nation, not the company with the service contract for Eastern Bumania.
Why? If a company in the UK or the USA sells a "bike widget" to "Bike Widgets of Germania", "Bike Widgets of Germany takes on the obligation to provide warranty service in Germany. A bike shop buys the widget from BWG, not from the factory. The factory has no obligations to the bike shop, nor to a customer that buys from the shop. Both the shop and the ultimate user must look to the company that sells the lock in Germany for warranty service.
This seems to be beyond the understanding of many consumers. Folks will buy a "bargain" Nikon camera while traveling through Hong Kong because it is cheaper than buying in the USA. They are stunned when Nikon USA refuses to do warranty work on the camera. Nikon USA only warranties the cameras it sells, and those cameras come with Nikon USA warranty papers.
There have been many reports of owners frustrated with their 2004 and 2005 model "flat key" bike locks. Yet, when those owners READ THE OWNER'S MANUAL (a shocking step for most men) and learn how to use a flat key lock, they have no problems. These locks require fully seating the key before turning it. This design makes it more difficult to pick the locks. This is explained in the owner's manual...just read it.
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