This procedure can lead to damage and severe injury if not obtaining safety rules. If you want to be on the safe side go with 65Hz unless the manufacturer doesn't give you another classification. We cannot tell you the specs of a servo unless we don't have any data of this specific servo ourselves. Please ask the servos' manufacturer. We do not produce or sell any servos, we only give you the possibility to use those servos. Therefore we do not accept liability for incorrect setting.