Originally Posted by
FBinNY
26.4 is the nominal, and the crown races themselves are dimensioned to that -0.00 +0.02mm. The cutters are made to cut 26.45 ±0.02mm so that provides for the interference. There's some latitude in the amount of interference, but there has to be some. However .2mm is more than a heat treated bearing race can accept.
Thanks.
Originally Posted by
FBinNY
Note also that modern crown races are not as substantial is their predecessor, so an amount of interference beyond ideal that might be tolerated in the past will crack a more modern crown race.
Makes sense, my last 20 yo race (Campy Croce d'Aune or maybe it was Chorus) lasted many 1000s of kms but I wanted to replace it because it was starting to become pitted (I was lazy and didn't repack as often as I should have).[/QUOTE]