Cleaning a chain properly takes ten minutes
For a year my chain was black, gritty and loud. Then a friend at the local shop showed me a routine that takes less time than making coffee.
The routine
Wipe the chain with a rag while backpedalling. Scrub with a little degreaser and an old toothbrush. Rinse, dry thoroughly, then apply one drop of lube per roller. Wipe off the excess — the outside of the chain should feel almost dry.
How often
A quick wipe after every wet ride, the full routine every few hundred kilometres. Check chain wear with a cheap gauge every couple of months.