Braking noise

If you must (and I never have) then what about metho? or isopropyl alcohol if you already have some?

Anyway, you need to clean both pads and rim and I just use a metal file to buff the pads and detergent for the rims. Check that your pads aren't worn down to the metal either or that there's no bits of rim stuck in the pads. Shimano pads are a bit shit for digging apart rims.

WTF Hippo? When did you become Captain Sensible?