The cams' curved surfaces compress fuel and release exhaust as they spin, generating 24 combustions for each crankshaft revolution.

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The "W12" refers to the 6.3-liter, 500-hp direct-injection engine, with four rows of three cylinders conjoined at the crankshaft.

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The V of the cylinder heads sticks out the sides of the motorcycle, and the crankshaft runs lengthwise, longitudinal to the bike.

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The faintest shudder, coming from many decks below, is your only sign that a 52-pound crankshaft has suddenly accelerated to 800 rpm.

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In most spark ignition engines, a thermodynamic cycle occurs when the piston completes four strokes within the cylinder, and the crankshaft completes two revolutions.

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The rotation of the crankshaft imparts a rocking moment to the chassis, so that these bikes lean to the right when you give them the gas and go strangely neutral off-throttle.

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