N.D. Cent. Code § 39-27-11

A seat or saddle securely attached to the vehicle must be provided for the use of the operator. The seat or saddle may not be less than twenty-five inches [63.5 centimeters] above a level road surface when measured to the lowest point on top of the seat or saddle cushion with the operator seated in a driving position. The seat or saddle adjustment locking device must prevent relative movement of the seat from its selected and secured position under all normal vehicle operating conditions.