As chores go, cleaning your chain ranks right up there alongside unblocking the toilet or creasoting the shed for sheer unwelcomingness. But it's one of those things that has to be done - a clean chain is a smooth-running, long lasting chain and nothing spoils a ride like a chain that sticks and slips and won't shift and then breaks. There are a few different approaches to chain cleaning, so pick the effectiveness/time compromise that suits you best...
1. If you happen to have a chain with a quicklink magic joining doofer than you can undo by hand, the most effective method is just to take the chain off and dump it in a container of suitable degreaser. You'll probably want to use a large, shallow container rather than, say, an empty tuna tin - if you can coil the chain up so it lies flat you don't need much degreaser. You can read more details about this technique here.
2. If you don't have a quicklink, splitting and rejoining the chain just to clean it is a bit of a performance, so you'll have to deal with it in situ. Shift into the gear with the straightest chainline you can find (middle chainring and fifth sprocket on 27 speed setups) so you can spin the cranks backwards without the chain wandering around the place. Use degreaser and a stiff-bristled brush to work it into the chain. It's a good idea to set aside a brush just for chain cleaning - they get pretty oily and tend not to get anything else very clean...
3. If that seems a bit longwinded, the slightly easier (and certainly less messy) option is a chain cleaner. There are loads out there, all essentially similar - the chain runs through a load of whirly brushes sat in a bath of degreaser and comes out nice and shiny.
4. Whichever method you choose, give the chain a good wipe down with a suitable rag (impossibly faded bike race t-shirts from the early 90s are a good choice). With a bit of practise you can hold the rag around the chain and wind the pedals backwards to run the chain through.
5. If you've used degreaser and a brush you may find it more effective to rinse the stuff off with some water. If you've done this, spray the chain with some thin water-displacing stuff like WD-40, GT85 or X-Lube. It won't be hefty enough to actually lube the chain, but it'll stop it going rusty.
6. Once the chain's nice and shiny and dry, reapply a proper chain lube. If you're in a hurry to start eating toast, you can lube it up just before the next ride. But if you can, doing it before you put the bike away gives the stuff time to get everywhere it needs to be and puts you one step nearer to ride readiness next time. We like lubes that come in squeezy bottles - they're more time-consuming to apply but it all goes where you need it. Putting the lube on over the cassette ensures that any that does wander at least ends up somewhere semi-useful.
More maintenance
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