Patent attributes
A camshaft support structure of an internal combustion engine (10) includes a camshaft (26, 30) that drives an intake valve (18) or an exhaust valve (20); a head cover (34) that houses the camshaft (26, 30); an upper bearing portion (42) which is provided on the head cover (34) and supports the camshaft (26, 30); a lower bearing portion (54) which is attached to the head cover (34) and makes a pair with the upper bearing portion (42) to retain the camshaft (26,30); a rocker arm (22, 24) that transmits driving force from the camshaft (26, 30) to the intake valve (18) or the exhaust valve (20); and a rocker arm support portion (56) that inhibits the rocker arm (22, 24) from falling out of position by being provided near and directly above the rocker arm (22, 24).