Bearing frame or cylinder head cover

An internal combustion engine, comprising:

• at least one of a bearing frame and a cylinder head cover;
• at least one camshaft tunnel-mounted in at least two bearing openings arranged along a bearing channel;
• and
• at least two radial bearings arranged on the camshaft and in the respective bearing openings, the at least two radial bearings each having an outer bearing shell;
• wherein at least one bearing shell includes a stepped outer contour and the associated bearing opening includes a complimentary stepped inner contour;
• wherein the outer bearing shells of the at least two radial bearings include variable outer diameters, the respective outer diameters being complimentary to an inner diameter of the associated bearing opening;
• wherein the inner diameters associated with the bearing openings decrease in a direction of assembly of the camshaft along the bearing channel.

A method for assembling a camshaft in a bearing frame or a cylinder head cover of an internal combustion engine, comprising:

• prefabricating the camshaft together with at least two radial bearing and at least one cams, the at least two radial bearings each including a bearing shell having a defined outer diameter,
• positioning the camshaft into a bearing channel of the bearing frame or the cylinder head cover, the bearing channel including bearing openings having inner diameters complimentary to the associated outer diameters of the bearing shells,
• arranging the at least two radial bearings into the associated bearing openings of the bearing frame or the cylinder head cover via an assembly aid,
• wherein the respective bearing shells of the at least two radial bearings include variable outer diameters and the complimentary inner diameters of the associated bearing openings decrease in a direction of assembly along the bearing channel.