In most shimano cup & cone bearings, the actual contact direction is quite close to radial. So the dirt line isn't important - the load is carried further out on the race, and that's where you need to check for pitting.
@moth started
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In most shimano cup & cone bearings, the actual contact direction is quite close to radial. So the dirt line isn't important - the load is carried further out on the race, and that's where you need to check for pitting.