Unlike the better balanced straight-six or even the ultra-smooth V-12 engine, the humble four-cylinder generates an up and down vibration with a frequency of twice the crankshaft's rotational speed.

不像运行起来比它更稳定的直列六缸引擎或者极其流畅的V - 12引擎，卑微的四缸引擎会以一种比自身机轴转速高两倍的频率产生一上一下的振动。

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