I've noticed with some alarm that on various bike forums you'll get posters waxing about their expensive security chains. Ever since I saw the first video I've been rather cynical about the claims of some chain makers (always was, actually) but to see the relative ease with which some very expensive and much-lauded security chains were cut, is a bit of an eye-opener.
OK, these are motorcycle chains, but the same principle applies as to bicycle chains; indeed, many bicycle security chains are even worse, being thinner to start with.
First, look at the popular makes
YouTube - Non-Almax security chains for bikes vs Bolt Croppers
Then look at the Almax
YouTube - Almax Series III and IV chains for bikes vs Bolt Croppers
I'm not advocating that everyone should immediately rush out and buy an Almax, for even that isn't proof against a 36V cordless angle grinder, but just bear in mind that the 100quid chain that's protecting your 1500 quid bike might be crapper than you think.
OK, these are motorcycle chains, but the same principle applies as to bicycle chains; indeed, many bicycle security chains are even worse, being thinner to start with.
First, look at the popular makes
YouTube - Non-Almax security chains for bikes vs Bolt Croppers
Then look at the Almax
YouTube - Almax Series III and IV chains for bikes vs Bolt Croppers
I'm not advocating that everyone should immediately rush out and buy an Almax, for even that isn't proof against a 36V cordless angle grinder, but just bear in mind that the 100quid chain that's protecting your 1500 quid bike might be crapper than you think.