Spherical Mates:

You can create mates using spherical bodies and surfaces. You can create mates between elliptical, conical, and parabolic edges, sketch entities, and other geometry that are related as follows:

• Coincident with a point

• Tangent to a line, circle, cylinder, sphere, or ellipse

1. Open assembly Ball Bearing.
2. Select Ball <1> and inside face of the outer ring.  Changed Mate alignment. 

3. In SolidWorks 2013 we were able to mate spheres tangent to spheres, planes, cylinders, and cones, such as the surface generated by this chamfer.

4. These limitations were removed for SolidWorks 2014. Now we can mate spheres tangent to edges. 

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5. Select 3d sketch and Ball and apply mate.​

6. Really mating spheres after SolidWorks 2014 gets much easier.