When it spending at over 8000 RPM, any imperfections will cause the crankshaft to become unbalanced and create potentially distractive vibrations through the entire engine.
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The engine must perform constant, controlled explosions with pistons, crankshafts, oil filters, alternators, fans, distributors, valves, coils, and cylinders among the many pieces of machinery needed for the work.
Within each of these cylinders is a piston, which moves up and down, spinning a bar known as a crankshaft, effectively converting linear motion into a rotary motion that can drive the wheels.