Whilst washing the bike last night I noticed the discs are badly pitted, not seen this before on any bike. It looks like poor steel as pitting is coming through as the disc wears.
New bike? Possible warranty claim?
Or could it be corrosion due to water being trapped between the pads and disc if the bike is washed and put away wet.? I always try and take mine round the block to dry the brakes out after washing it after noticing rusty marks on the discs.