| 摘要 |
In an SOHC-type engine in which first and second insertion/removal guide sections for guiding the insertion and removal of first and second spark plugs, respectively, are provided on a cylinder head including an intake valve and the first spark plug disposed therein and arranged along an axis of a camshaft, and an exhaust valve and the second spark plug disposed therein and arranged along the axis of the camshaft, a single rocker shaft (55) is fixedly disposed above the camshaft (34), and an intake-side rocker arm (59) moved following an intake-side cam (57) to drive the intake valve (47) and an exhaust-side rocker arm (60) moved following an exhaust-side cam (58) to drive the exhaust valve (48) are carried commonly on the rocker shaft (55). The first insertion/removal guide sections (68) and the intake valve (47) are disposed so as to be superposed one on another at least partially in a view of projection onto a plane perpendicular to an axis of the camshaft (34), and the second insertion/removal guide section (69) and the exhaust valve (48) are disposed so as to be superposed one on another at least partially in a view of projection onto the plane. Thus, the width of the cylinder head (22) in a direction perpendicular to the axis of the camshaft (34) can be set at a small value. <IMAGE> |
