AIR-COOLED, SINGLE-CYLINDER INTERNAL COMBUSTION ENGINE, SADDLE-TYPE VEHICLE, AND METHOD FOR PRODUCING AIR-COOLED, SINGLE-CYLINDER INTERNAL COMBUSTION ENGINE

摘要

A cylinder head body (100) constituting part of an air-cooled, single-cylinder internal combustion engine and integrally formed from an aluminum alloy by die-casting, wherein the aluminum alloy contains 8.0-12.0 wt%, inclusive, of Si, 0.5 wt% or less of Cu, 0.002-0.02 wt%, inclusive, of Sr, 0.2-0.5 wt%, inclusive, of Mg, 0.5-1.0 wt%, inclusive, of Fe, and 0.3-0.6 wt%, inclusive, of Mn. The thermal conductivity of the cylinder head body (100) at 100°C is 145 W/(m·K) or higher, and the Rockwell hardness of the cylinder head body (100) at room temperature is 70-90 HRF, inclusive.