PURPOSE: To make the outer peripheries of a collar be narrow and thin and prevent a collar from deforming by rotatably inserting the collar into a shaft hole through a bearing, rotatably mounting a reinforcing rings on the outer peripheries of both ends of the collar, inserting and clamping the support shaft of the end of a link.

CONSTITUTION: The bearing sections of a link 4 and link 5 comprises a collar 11 rotatably inserted in the shaft hole 9 of either the link 4 or 5 through the bearings 10 and reinforcing rings 12 fitted on the outer peripheries of both ends of the collar 11. In addition, a support shaft 13 to be inserted in the end of the other link is inserted into the collar 11. On both sides of the collar 11, a thrust washer 14 and a dust seal 15 are arranged. The rigidity of the reinforcing ring 12 is improved by reinforcing both ends of the collar 11. Since the reinforcing rings 12 are inserted into the gaps on both outsides of the bearing 10, it is not necessary to enlarge the internal diameter of the shaft hole 9. Therefore, the collar is prevented from deforming and cracking resulting in the improvement of endurance. In addition, the wall thickness of the collar can be made to be thin, and the internal diameter of the collar can be made to be small, as a result, a bearing device having mechanism used for suspending rear wheels of a motorcycle can be miniaturized and lightened.