Out last on bike and got something on my rear rotor making a right noise.I want to go out in the next few hours and can’t be arsed to go to the shop is there anything else I can use instead of disc cleaner.

IPA & no I don’t mean the beverage version.
What got onto them though? as pads could be contaminated & need cleaning/replacing as well

boiling water, fresh from the kettle.

I usually find going down a big hill dragging the brake burns most stuff of.

muddy puddle.

Its just a piece of stainless steel, so wash it. Normally thats all you need to do. Or clean it with petrol / meths or such like. That may leave a tiny residue on which is why some talk of IPA which wont. You may want to go over it with some emery paper to roughen it up a bit.

But if your discs got contaminated then change your pads as well.

If its making a noise that does not mean you have something on the disc. The noise is the high speed vibration of pad and disc, so perhaps the pistons have not fully retracted as they are dirty, or one of the pad spring clips is touching the disc.

Clean it, fresh pads, bed them in and you should be fine.

I usually find going down a big hill dragging the brake burns most stuff of.

muddy puddle.

If you’ve got something oily on there, that won’t work. Trust me.
Do this instead:

Take off disk
Douse in meths
Set light to it
Repeat.

Take off pads
Clean with emery cloth or wire brush

Refit both
That should work. 🙂

IPA is best but assuming you haven’t got that then warm soapy water and a bit of elbow grease is fine. You don’t want to knacker the pads and caliper seals with oily stuff like meths and nasty solvents or boiling water. You’ll need to bed the brakes in again if you thoroughly clean the rotors.

Leading on from this advice (I had a squealing front brak all day Thursday) what is the “best” way to bed brakes? Excuse the numpty question!!

Get up to bout 20mph and brake hard, repeat Several times.
Best off on big hill to build up heat, also must be dry.