Here is a trick I practice to free up rear axle bearing when mounting them with vintage style stamped flanges. Those flanges can place excessive pressure on the outer bearing race, since the tolerances are not closely controlled, a little tweeking as shown in the video below solves this. Alternatively, shimming between the flanges could be used, but I prefer modifying the flanges as shown in this video. This method essentially trues up these flanges so they fit the bearing more uniformly and accurately, shimming doesn’t accomplish this. Give it a try!  – Jeff Campbell

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