Timing chain system of engine having adjusted phase

PURPOSE: To provide the timing chain system of an engine, capable of reducing noise by changing a pattern of collision sound generated by the contact of a chain and a sprocket and a pattern of sound generated by the chordal action. CONSTITUTION: In a timing chain system 200 of an engine, a crankshaft sprocket 202 is connected to a crankshaft 205, and a cam shaft sprocket 204 is connected to a cam shaft 203. Respective sprockets are substituted, for sprockets 208, 210 offset at a half pitch. Chains 212, 214 having inward teeth are respectively wound between the sprockets 208 and between the sprockets 210.