I recently picked up a 1984 Vista Cavalier 3 speed. I serviced the crank, front wheel and head set bearings. When I was tightening the fork top nut it shattered. Apparently it is aluminum, it is not magnetic. Does anyone have a top nut for this bike? A 30mm wrench fits (best I can tell, see photo). The steer tube measures 25.4mm/.996in. Thread pitch is 1.0mm.