Splined hub front marked?

[nefematic]

On fitting new rotors I noticed a fine marked line on the inside flange of the hub, as well as the same line corresponding on the mounting surface of the old (maybe original?) rotor. The new rotor shows no mark. Surely no special fit to consider when fitting the new rotor? I've already fitted the nearside so I can't check there. My old rotors have the outside ring, would that possibly be original part?

Thanks,
Martin

Hub:


Old Rotor marked:


Old Rotor outside ring:

[christopher storey]

It's not something I have ever seen before , Martin, and there is no reference to it in any workshop manual. Maybe someone in the past has balanced the hub and the rotor separately for some reason , although this would be a very unusual thing to do . I should just fit the rotor in any convenient position and bolt it together