Stolen bikes

1) Post a pic?
2) Which product? There seems to be loads.
3) How much shaking and ratteling before the alarm goes off? Wouldn't want it to start blaring away if someone, say, moves my bike slightly because they are trying to lock their own bike next to it.

I can't take credit for inventing a product or anything like that, but I think I'm the person who has suggested this particular motorcycle solution for bicycles.

I suggest buying a red or yellow disc lock alarm, as those colours stand out. A silver alarm might not be so bad when attached to a black chainring/crankset. http://ecx.images-amazon.com/images/I/41tNasb-mmL.jpg, http://www.blacksheepcycles.com/Photopost/data/520/medium/SNC11681.JPG

As for which exact disk alarm lock, I can't tell you that. But brighter, louder, and least expensive, seem to be a winning combination. But disk alarm locks like the one pictured, are ideal, as they are so snug to the ring, that they cannot be cut off. It would be easier to cut off the chainring, or take off the whole crank. And which thief would ever do that?

As its a theoretical solution, I also can't give figures for how much or little vibration, movement is required to trigger the alarm. I'd be happy to simply reset it, if I was in a pub having a drink, and it went off.

I think if more and more people tried this, and there were obvious brightly coloured alarms attached to chainrings, I think theives would start looking at chainrings first, even before crossing the street with their bolt cutters. After all, they won't know where the owner is.......