| 摘要 |
PURPOSE:To prevent a petal pattern from being formed when honing the inner surface of a cylinder sleeve, by tilting double side edges of the cylinder circumferential direction of a scavenging inlet to the cylinder longitudinal direction. CONSTITUTION:A cylinder sleeve 18 is attached to the inner surface of a cylinder 10. And, a crankshaft side end of this cylinder sleeve 18 is notched, and a scavenging inlet 26 is formed as opposed to a crankcase 20. Likewise, a scavenging outlet 28 to be opened to the inside of the cylinder 10 is formed in a spot little to the center of the cylinder sleeve 18. And the scavenging inlet 26 and the scavenging outlet 28 both are interconnected with each other through the scavenging passage 32 formed in a cylinder block 30. In this constitution, the scavenging inlet 26 is formed into an equilateral triangle having the apex situated at the top dead center side of a piston 12. That is to say, double side edges 38 of the circumferential direction of the cylinder 10 at the scavenging inlet 26 is tilted to the longitudinal direction of the cylinder 10. |
