kgf/mm

kilogram-force per millimeter

Spring constantexact by definition

The kilogram-force per millimetre is exactly 9806.65 newtons per metre. It is the spring rate unit of Japanese and older European automotive practice: coilover and suspension spring rates are catalogued in kgf/mm, and 8 kgf/mm is a common sport setting.

Watch out: Roughly, 1 kgf/mm is 56 lb/in. Suspension rates cross between kgf/mm, N/mm and lb/in in the same conversation more often than any other stiffness unit, and the three differ by factors of 9.8 and 56.

1 kgf/mm 9,806.65 N/m