For those who have a notchy advance mechanism bearing, the number is 6813Z, which can be obtained from any decent bearing supply house.That size is 85mm OD, 65mm ID, 10mm thick.
Till then, lube them as other members have advised. They are shielded, but lubricant can be infused through the inner edge of the shield. CZ
Till then, lube them as other members have advised. They are shielded, but lubricant can be infused through the inner edge of the shield. CZ