Originally Posted by
Paranoid.Guy
What are the tools that could defeat a good bolt-cutter-proof security chain?(except the angle grinder).
As has been stated security chains aren't "bolt-cutter-proof", but even if you can assume your chain will withstand the bolt-cutters most thieves would be using you still have to use something to lock the ends together.
A heavy chain and a shrouded contractors padlock is a fairly effective combo, but very very heavy. And with key locks there's always the chance someone will tamper with the lock so you can't open it (and most combination locks are ridiculously easy to open).
And to make you really paranoid I've seen two completely stripped frames still locked to bike racks, and one that was just missing the front fork (the front wheel was still locked to the frame).