The areas around the control ring accumulate various kinds of grime over time. I have a feeling that adding oil might help in the short term but hurt in the long term by holding the grime that accumulates there. I've had my eVic since Dec 2012 and the 2 times the control ring started to get a little sticky I did the dental floss thing. The ring worked like new after a couple of minutes. I've never felt the need to use a lubricant of any kind.