Sounds like that might be the grease port; there was one on an old Record track hub I used to have. It's there so you can inject grease on to the bearings. You do not need to remove it to service the hub. A photo might help confirm this.
@deleted started
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Sounds like that might be the grease port; there was one on an old Record track hub I used to have. It's there so you can inject grease on to the bearings. You do not need to remove it to service the hub.
A photo might help confirm this.