I am working on 1985 K100 which seems never spent a single day in a garage and possibly has not seen any service whatsoever… I took apart the bike and was going to replace headstock bearings today, which were completely seized. I finally dislodged remains of bottom bearing, but there is what appears a bump or bent lip on the stem, which prevents it from sliding off. Is this something done on purpose during assembly,
? Is it OK to grind it off to remove the bearing? In a separate question, when installing new races, do I need to heat head tube, or freeze race to facilitate installation? Or just whacking with mallet will suffice? Thank you.