Hi Dan,
Where did you get the bearings from? Reason I ask is Pete Reed solved a similar issue for me a few years back. I had bought Boca high performance class bearings for my Nelson and had the same issue as you. Pete suspected the bearing had too much " preload" and gave me a set of bearings from Henry and it went away. Pete was a bearing engineer by trade, a wealth of information and a great guy-sure miss him

Lewis