Many London motorcyclists are worried about bike thefts. The best security chain I’ve tried is the heavy- duty, police-approved, 19mm Protector 1.5-metre, supplied with a Squire lock, by British firm Pragmasis.
The makers say it’s “impossible” to cut with any known commercially available manual bolt croppers. This “Sold Secure Gold”-rated chain (6.3kgs per metre) is £119.95 for the chain or £184.95 with the padlock.
It’s a bit heavy to carry around and slightly trickier to feed through the bike. But they produce “anti-pinch pins” (from £35) to fit through tight spots and lock into the chain.
More at securityforbikes.com