I have had these Dual air Revs since 2007. They used to work brilliantly with excellent small bump sensitivity. Over time they seemed to get slower, handling big bumps fine but losing responsiveness to smaller bumps. I recently changed the oil to see if that would help but they are still the same. Is this a symptom of needing to renew seals or something?
To clarify, this is not stiction, they freely move, its more like they have loads of compression damping or something.

