What are balance shafts for?

Balancing shafts are designed to eliminate vibrations and uneven engine operation by compensating for the forces that occur in the crank-piston system.

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In engines balanced by this method, two shafts are placed, driven by a crankshaft. The shafts rotate in opposite directions at twice the speed of the crankshaft. In common parlance, it is determined that engines with such a balance are characterized by a higher “culture of work”.