Senmou Main Line jointed two major cities in eastern Hokkaidou, Abasiri and Kushiro. It was called “Main Line,” but actually it was just a local line. Abashiri side of the line faced to Okhotsk Sea that was filled by drift ice in winter. Kushiro side passed through Kushiro swamp. The locos served there were JNR C58 class.
JNR C58 Class
C58 class was designed for local line passenger and freight trains and manufactured from 1938 to 1947 and only one example of 2-6-2 axle arrangement in JNR. They were quite versatile in operation.
However the swinging movement in yawing axis was quite large comparing to other models. I noticed such a swing only with this class. Short connecting rods of the class were suspected of this swing.