Bearing lube for Dynavector tonearm

I own a Dynavector DV505 that has been idle for many years. I now want to install it, and I noticed that there may be a bit more friction in the horizontal bearing than I am used to, compared to my other DV505 that is in constant use. There is absolutely no rubbing sound or real resistance to rotation about the bearing axis, but just a tad less sense of freedom of movement. Does anyone know about lubricating the DV tonearm bearings? Is it periodically recommended or are these sealed bearings that should be left alone? If it should be done, what lubricant is favored? I put this question to the US distributor, and he is trying to find out from Dynavector Japan, but I thought I would bring it up on this forum. Thx.
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The Damper plate is very easily bent.
Maybe it is rubbing a touch on the damper magnet ?
Just another thing to check.
Dear Mink and Ct, there is no detectable binding, just audiophile nervosa. Damper plate is perfectly aligned. I actually think that what I may be sensing is simply the damper plate doing its job; if you swing the horizontal arm manually, at a much faster rate than what happens when you play an LP, then the dampening effect is increased and creates a tiny amount of drag in proportional to velocity, I am guessing. The only tiny bit of substantive evidence that any servicing is needed is that this sample seems to have a tiny bit less freedom of horizontal movement compared to my other DV505, which has been in constant use for a few years. (I bought two, because the DV505 has a flat mounting plate that does not require drilling holes, and I was making slate plinths for two or three tt's at the time. I did not fancy drilling holes to mount tonearms in slate. Surface mount tonearms were easier to contemplate.)

In the DV507 Mk2 owners manual there is a photo of the collection of ball bearings used in various parts of the arm structure. They look to be of high quality but not very exotic. Don't know whether they are meant to be oiled or not, Elizabeth. Perhaps the factory will eventually tell me via the auspices of the US distributor.