I am about 10 kg above a good cycling weight so that is more significant than the weight of the lock, but hanging a chunky 1.7 kg metal object off a lightweight bike would feel like a bit of a backward step!
I don't usually go too far from my best bike unless someone else is watching it for me, or I am leaving it somewhere very quiet so I don't really need that degree of security. It will be good for securing my singlespeed bike outside local shops though. We do have thieves round here too, but crime rates are not like those in a big city. It would be a big surprise if someone thought it worth the risk of cutting that lock off a cheap home-made bike right in front of a busy supermarket. (I have probably jinxed the bike now and it will get nicked within weeks!

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