RSA 266:18-c General Weight Provisions.

The following provisions shall apply to any vehicle covered by RSA 266:18, 18-a, or 18-b, regardless of the type of way or highway on which it is driven, except as otherwise specified:
I. A vehicle or combination of vehicles equipped with any solid rubber tires shall not have weights more than 80 percent of those permitted; provided that no vehicle equipped with solid rubber tires which has at any point less than one inch of rubber above the top or beyond the flange or rim shall be driven upon any way.
II. Motor vehicles or vehicles drawn by motor vehicles when equipped with metal or other hard tires shall not have weights more than 40 percent of those permitted.
III. The provisions of RSA 266:18, 18-a, and 18-b shall not apply to vehicles used exclusively in the s