No person shall drag or propel any vehicle, machine, harrow, cultivator or implement of any kind over, along or upon any street, alley or other public place which does not wholly rest upon adequate road wheels which do not damage or cut into the street, nor shall any part of such machine or other vehicle, other than the wheels carrying the same, come in contact with the surface of the street, except that light orchard cultivators and similar implements may be transported on light drags over and across unimproved streets if it is done in such a manner as not to cut into or make ruts in the streets.
(`78 Code, § 12.20.050.)