| 摘要 |
<p>The cylinder is cast from a light alloy (1). It has an internal ring (2) also made from light alloy fitted to join the valve and inlet or exhaust ports. The ring may also be fitted in the bore to form a wall for the passage of gas between the cylinder and crankcase, and guide the piston past bottom dead centre. The ring is fitted to small cylinders and can be mechanically retained by a stop.</p> |
