Figure 1.1 shows a four-cylinder engine that has the two outer cranks at 120 to each other and their reciprocating masses are 400kg. The distance between the planes of rotation of adjacent cranks are 0.4 m, 0.7 m, and 0.5 m. The length of each crank is 350 mm, the length of each connecting rod is 1.7 m and their engine speed is 500 rpm. Determine, 1.1. The reciprocating masses and the relative angular position for each of the inner cranks, if the engine is to be in complete primary balance. (draw the primary and secondary couple polygon) [22] 1.2. The maximum unbalanced secondary force. [12] 0.4 m 0.7 m 0.5 m Figure 1.1 four-cylinder engine