Maintenance of barbell usually includes two aspects:
No matter barbell with cerakote or other coating, or even bare steel barbell, they need to be lubricated in regular; the frequency depends on how often you use the barbells.
There are two concepts: lubricant oil and grease
Lubricant oil is mostly used, but grease is also a good option, if you don’t want to do the maintenance frequently, you may apply the grease which could keep for a longer period, and it seals well to prevent dirt out of sleeves, and it could reduce the noise when spinning, also it can reduce the vibration, so it would be better to use on low speed rotate power lifting barbells; and lubricant oil would be suitable for weight lifting bars.
Cerakote Barbell or Ceramic Barbell basically does not require frequent cleaning, only due to its anti-corrosion characteristic, but as you know, the chalk or the dirty left in the knurling would influence the hand grip feeling, so cleaning with brush is necessary also.
Proper maintenance would definitely extend the span life of barbells.
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