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New bike chain

I replaced my bike chain on the weekend. I’ve been thinking I’ve needed to do this for a quite while, based on the 12-inch chain pin-to-pin measurement. That length was over the “small weird imperial measurement” that the literature recommends — it’s about 2 mm I think, but “2 mm in 12 inches” feels like a strange way to put it. So I bought a chain gauge! And it’s great: clean the chain, plonk the gauge on, and immediately know whether the chain needs replacing. The new chain (a Shimano HG93 9-speed) was $27.90, which is less than that plus a new cluster and maybe chainrings, so it feels like it’s worth doing regularly.

While I had the wheel off I thought I’d repack the bearings, which turned out to be annoying. I’ve not had a bike with a rubber dust cover before, and couldn’t figure out how I was supposed to get the cone spanner on while keeping the dust cover in place. Of course, it’s not meant to be done like that, and thanks to the Park Tool website I learnt that the rubber cover could be stretched into place after everything else had gone back together. Much easier. I am however still pretty bad at getting the position and tension of the two bearing cones correct, and had to put it all together and take it apart again about three times before I got it right! Oh well, all is running well now.