new brake pads grinding noise

New pads can rasp a bit at first; a light grind for the first 50–200 km while they bed into the rotors is normal. If it is loud, constant, or worsening, something is amiss and it is not just your ears. Perform a proper bed-in with a few medium stops from speed, then let them cool, and recheck. If in doubt, park it and get a technician to listen—cheaper than buying new rotors after a week of abuse.

• Debris or a small stone caught between pad and rotor.
• Cheap or high-metal-content pads causing abrasive contact.
• Unmachined or lip-worn rotors glazing the new pads.
• Missing shims or poor fitment; pads not chamfered or seated.
• Sticking caliper slides or piston causing uneven pressure.