The research considers methods of motor graders rise of efficiency by perfecting constructions of cutting elements and working organs on the basis of rise of a resource of their work. The work contains a research of interdependence of parameters of motor graders working organs by statistical methods with the purpose of detection of the basic tendencies of their development. The basic directions of designing of motor graders working organs and most perspective constructions are detected by a method of analysis of patent solutions. The formulas for account of resistance of ground to cutting by a knife with one direct and two sloping cutting edges with allowance for an angle of declination of a knife and its wear are deduced. The regularities of a wear of the cutting elements of a blade are investigated, its influence to efficiency of work and on parameters of working organs design is detected. The maximum size of wear is determined. The requirements to motor graders working equipment are defined on the basis of conducted researches, the new constructions of multiple use knives and order of their sequential replacement are developed in correspondence with the research work. It ensures the raise of efficiency of the machine by 10…15 per cent and it increases resource of knives in comparison with a traditional construction 3…4 times as much.