I also have a set of Class 3 bearings on the way, so one way or another were going to find out eventually if thats it. I plan on exhausting everything before that, I would rather not loose the ones that are in there but. I am also looking into replacing the other bearing in the headstock the non-spindle bearings. Any chance they were class 3 or above. The book calls for some to be Timken and some to be New Departure, but no numbers. But I can see those without tearing down the headstock.