I'm thinking nine quid a litre is taking the pish. Any suggestions for a reasonably enviro-friendly cassette & chain degunker? Nine quid a gallon preferably
petrol or white spirit, if you don't throw it away. leave it to stand and decant off into another container (1 litre oil bottles work well). When you have enough left over oily sludge dispose of it down the local tip.
washing up liquid, there is a lot of crap talked about the damage it can do, the tiny amount of salt it contains is nothing compared to the harshness of conditions that a mountain bike operates in.
Chain and the like I have an old tin that's full of white spirit...it's murky as hell but it still does the job then I just clean it down in washing up liquid dry it and regrease it