Soak kombu in warm water. Wash. Cut into 5 or 6-inch pieces. Wash kampyo. Cut pork into strips about 1/2 inch thick and 2 inches long. Wrap one piece of pork and gobo in kombu strip and tie with kampyo. Pack komubu maki into a saucepan. Add water and cook over low heat 1 1/2 to 2 hours or until tender. Add shoyu, salt, sugar, and sake. Simmer for 30 minutes more.