The Starting Motor assembly is constructed from several parts from which the Motor Assembly,starting is the most expensive.
The most reasonably priced component used on the Gsx600f Katana 1990 (l) Usa (e03) Starting Motor is the O Ring(d:3,id:24.5).
The sixteen Gsx600f Katana 1990 (l) Usa (e03) Starting Motor component parts are all listed in this schematic.