View Full Version : Early motorcycle fork bearings

1st Jan 2018, 10:30 PM
I have been chipping away at a motorcycle project for a long time, its a 1924 Ace. The latest puzzle is the front fork bearing races. The setup is as the photos show, an inner race is just the cone feature on the knurled nut (photo 1), those have been remade quite some time ago. Its now my task to make the two spigoted outer races, these have been badly brinelled/dinted from hard impacts over the years.

They are reasonably hard but nowhere near as hard as a modern bearing race, I would say somewhere like 40 - 45 rockwell. they dont show signs of being ground just turned but do seem to have been nickel plated. the balls were just packed in with grease no cage.

My questions are:

Would the inside of the race really have been plated, I dont think nickel would really hold up even in a low force, low speed, high load situation like this, unless its harder and more robust than i think.

How should i go about grinding that ball form into the cup, I do have a rudimetary tool post grinder, just a ball tip on that? I would think it might be quite a load grinding all that surface area.

Should I go for a higher hardness for better impact resistance or do i need the toughness?

Normally i would just shove a tapered roller in there but in this case it needs to be kept original. Note there are two identical setups, top and bottom of the fork housing

Regards - Ralph20171231_125007.jpg (http://metalworkforums.com/attachment.php?attachmentid=371511&d=1514804246)20171231_125023.jpg (http://metalworkforums.com/attachment.php?attachmentid=371512&d=1514804428)20171231_124957.jpg (http://metalworkforums.com/attachment.php?attachmentid=371513&d=1514804529)20171231_124953.jpg (http://metalworkforums.com/attachment.php?attachmentid=371514&d=1514804561)
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