Fenwicks’ FS-1 Bike Cleaner may appear expensive on a like-for-like quantity basis, but you can either use it as a concentrate to shift determined gunge on chains, cassettes and the like, or dilute it with one part FS-1 to 10 parts water to use as an all-purpose bike cleaner.
Once you’ve done that, it provides a good, no-frills level of cleaning, but it will require some rub-a-dubbing on your part. It won’t discolour any of your components, and it leaves your bike clean and shiny with no residue.
We didn’t like the dropper for concentrated application, but the large-size availability, which you can decant and dilute into a cheapo container (or a rinsed-out household cleaner bottle), has to be a good thing in terms of minimising resource use. And once you’re done with the big bottle, it can be recycled.