CAMSHAFT BEARING STRUCTURE

A camshaft bearing structure includes a bearing part (4) which has a journal hole (1) that is defined by an upper part of a cylinder head (5) and a cam cap (6) that is assembled to the upper part of the cylinder head (5) and rotatably supports a camshaft (2), and a pin ring (16) that is press-fitted into the cylinder head (5) and the cam cap (6) to determine the position where the cylinder head (5) and the cam cap (6) are assembled to each other. In this bearing part (4), the pin ring (16) is provided only in an inner part (14), which is a part of the bearing part (4) between the axis (L) of the camshaft (2) and the center (13) of an upper part of the cylinder head (5).