Crankshaft drive for an internal combustion engine

A crankshaft drive in an internal combustion engine, which comprises

• (a) at least one cylinder having a cylinder head defining a space,
• (b) a crankcase housing
• (1) a crankshaft rotating at a predetermined direction and at a predetermined speed, and
• (2) a balance shaft extending parallel to the crankshaft and rotating at the predetermined speed of the crankshaft in a direction opposite to the predetermined rotating direction of the crankshaft,
• (3) the crankshaft and the balance shaft carrying balance weight means for balancing a mass of first order,
• (c) an auxiliary shaft supported on the cylinder head and extending parallel to the crankshaft and rotating at the predetermined speed of the crankshaft in the predetermined rotating direction of the crankshaft, the auxiliary shaft
• (1) carrying a counterweight for balancing a residual moment resulting from the rotating balance shaft with respect to the rotating crankshaft, and
• (2) an axial blind hole opening outside the cylinder head space, and at least one bore extending transversely thereto from the blind hole to communicate with the cylinder head space, and
• (d) a camshaft drive in the cylinder head space for driving the auxiliary shaft.