The Bore is the diameter of the cylinder. The stroke is the distance the piston travels from BDC (Bottom dead center) to TDC (top dead center). The Bore is always mentioned first.
内径指的是气缸的直径；行程是活塞从下止点运行到上止点的距离。表述时，内径总是写在前面。
2
The diameter of the cylinder is called the engine bore.
气缸直径被称为发动机缸径。
3
The diameter of the cylinder is called the engine bore.