§ 71.21 MAXIMUM LIMITS.
   (A)   Except when a special hazard exists that requires lower speed for compliance with § 71.20, the limits set forth in this section and Neb. RS 60-6,187, 60-6,188, 60-6,305, and 60-6,313 shall be the maximum lawful speeds unless reduced pursuant to division (B), and no person shall drive a vehicle on a highway at a speed in excess of such maximum limits:
      (1)   Twenty-five miles per hour in any residential district;
      (2)   Twenty miles per hour in any business district;
      (3)   Fifty miles per hour upon any highway that is gravel or not dustless surfaced;
      (4)   Fifty-five miles per hour upon any dustless-surfaced highway not a part of the state highway system;
      (5)   Sixty-five miles per hour upon any four-lane divided highway not a part of the state highway system;
      (6)   Sixty-five miles per hour upon any part of the state highway system other than an expressway, a super-two highway, or a freeway.
   (B)   The maximum speed limits established in division (A) may be reduced by the Department of Transportation or the Board of Trustees pursuant to § 71.23 or Neb. RS 60-6,188.
   (C)   The Board may erect and maintain suitable signs along highways under its jurisdiction in such number and at such locations as it deems necessary to give adequate notice of the speed limits established pursuant to division (A) or (B) upon such highways.
(Neb. RS 60-6,186) Penalty, see § 71.99