由于低发动机罩和短行程发动机的进一步普及，半围延裙活塞和滑裙式活塞开始使用。

As lower hood lines and over square engines became popular, the semi-slipper and full-slipper pistons came into use.

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使用滑裙活塞的原因是：短行程发动机需除去部分活塞裙部，从而为曲轴的平衡重让出空间。

One reason for the slipper piston is that, on the short-stroke, over square engine, the piston skirt had to be cut away to make room for the counterweights on the crankshaft.

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