Don't assume that your 'replacement' has standard size journals, a previous owner may have had it reground, old shells may say if they were oversize but best to measure it up before ordering the bearing shells.
If I were being pedantic - who me? the shells are oversize (compared to standard thickness) to compensate for the undersize crank journals! but I get what you mean.Pistons come in oversizes. Ground cranks and crank shells are undersized.
If I were being pedantic - who me? the shells are oversize (compared to standard thickness) to compensate for the undersize crank journals! but I get what you mean.