I second dirty pads/rotors. Cleaning sometimes works but new pads and a clean rotor is better. If he's not doing anything huge I've found resin pads to be a bit less squealy.
@snottyotter started
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I second dirty pads/rotors. Cleaning sometimes works but new pads and a clean rotor is better. If he's not doing anything huge I've found resin pads to be a bit less squealy.