MickeyDBC
Gold Member
I would imagine that these are ABEC 1 (industry standard tolerance) bearings along the lines of automotive wheel bearings. These bearing sizes are often available in an ABEC 3 or even 5 standard (much tighter tolerances) that will give better performance and life. Generally a bearing supply house can cross reference the stock bearing to a higher quality SKF or FAG bearing, often for the same price as the original equipment bearing.