Master Rod (Reciprocating Engine)
The only rod in a radial engine that connects a piston directly to the crankshaft. The crankshaft of a radial engine has only one throw for each row of cylinders, and the large end of the master rod rides on the journal of this throw. The small end of the master rod is connected through a wrist pin to one piston. The pistons on all the other cylinders in that row attach to link rods, or articulated rods, that connect to the master rod through knuckle pins.