Although the usual recommendation is to use one of the Kluber greases, after a discussion with one of the other members I used Chevron SRI-2 spindle grease because I was reusing my bearings and Chevron SRI is intended for spindle bearings. The dN number of the bearing is dN= diameter in mm X spindle speed). I used the average of the inner and outer races for my diameter and a spindle speed of 3600 RMP. The dN for these two bearings is roughly 122,400 and 129,600. Even using the diameter of the largest outer race 52mm instead of the average diameter, the dN works out to 187,000. The capability of SRI grease is up to 400,000 dN. Kluber NBU-15’s capability is 850,00 dN and Kluber NCA-15 is 1,300,00 dN by comparison. If I were using new bearings, I’d probably follow the recommendation to use Kluber.
I greased my bearings using a syringe and needle. The rear bearing (Barden 204H) is reported to require 1.5cc of grease and the front bearing (Barden 205H) 2.0 cc of grease. To my eye, these amounts yielded a bearing fill of approximately 50%. Fill recommendations vary but seem to be around 25% to 30% or a match-head or BB sized blob between each ball. Nevertheless, my bearings did not get hot with 1.5 and 2.0 cc of grease when I ran them in.
Grease the bearings and put them in a baggie until you’re ready to install them.
Turn your attention back to the spindle. Examine the bearing surfaces with magnification. The recommendation on the net is to lightly stone any scratches.
After stoning the spindle, clean it, then oil it (I used Dexron transmission oil), wrap it in plastic kitchen wrap and put it in the freezer for a couple of hours to shrink it. The oil and kitchen wrap are to prevent condensation when you remove it from the freezer. When it was time, I warmed my front bearing on a 100 Watt trouble light until it was about 300º+ (10-15 minutes). When I placed it on the chilled spindle, it literally dropped in place. The side with the writing / small diameter side faces toward the interior of the spindle. Install the tabbed washer adjacent to the front bearing. Note that one tab is bent toward the front of the spindle and rides in the keyway. Tighten the slotted inner nut until it firmly holds the bearing on the spindle. Bend a tab into an open slot on the nut.
Using a heat gun (hair dryer if you don’t have one) warm the spindle housing until you almost can’t stand to put your hand on it. Again this heating is enough to allow the bearing to be pushed into the housing with hand pressure.