Secondary air supply passage for an engine

摘要

A secondary air supply passage joins a reed valve chamber provided on a cylinder head cover and an exhaust gas port. The secondary air supply passage includes three aligned passages formed in a cylinder head, a cam holder and a cylinder head cover. The secondary air supply passage is formed perpendicular to a cylinder head gasket. One end of the secondary air supply passage opens to a secondary exhaust gas air induction part, formed integrally with a core of the exhaust port, during casting of the cylinder head.