Abstract: A rolling bearing for a rocker arm includes an outer ring in rolling contact with a cam of an engine, an outer-ring shaft placed inside the outer ring and fixed to the rocker arm, and a plurality of rollers provided between the outer ring and the outer-ring shaft. At least one of the outer ring, the outer-ring shaft and the rolling elements has a nitrogen-rich layer, an austenite crystal grain size number in a range exceeding 10, and a surface hardness Hv of at least 653. Thus, the life can be extended.

Abstract: An improved roller bearing assembly of the type comprising an inner race having a cylindrical riding track; an outer race coaxial with the inner race, having an inner cylindrical riding track facing the outer riding track of the inner race; and a series of rollers mounted between the riding tracks. This roller bearing assembly is improved in that each of its rollers has at least two cylindrical riding surfaces of different radii, the cylindrical riding surface of longer radius exclusively contacting the outer race riding track while the cylindrical riding surface of smaller radii exclusively contacts the inner race riding track. The radius of the riding track of the outer race equals the sum of the radius of the riding track of the inner race plus the longer and smaller radii of the riding surfaces of one roller. The ratio of the radius of the riding track of the outer race over the radius of the riding track of the inner race equals the ratio of the longer radius over the shorter radius.