Bearing cage and bearing

A ball bearing, comprising:

• an inner ring comprising a raceway and at least one circumferential groove in an outer diameter surface of the inner ring,
• an outer ring;
• a plurality of rolling elements disposed between in the inner ring and the outer ring;
• and
• a bearing cage positioned between the inner ring and the outer ring, the bearing cage comprising:
• a generally annular backbone portion having a front side and an opposite back side,
• a plurality of cantilever portions extending from the front side of the backbone portion, the cantilever portions being arranged along a circumference of the annular backbone portion and defining a plurality of pockets receiving the rolling elements, and
• a plurality of grooves formed in the radially inner side of the bearing cage,
• wherein at least one circumferential groove of the inner ring at least partially overlaps with the plurality of grooves of the bearing cage in an axial direction of the ball bearing, and
• wherein a portion of the plurality of grooves of the bearing cage extends over the raceway and has an axial dimension of L3, and a bottom of the plurality of grooves of the bearing cage is spaced from the outer diameter surface by a distance L4,
• wherein
• L3>0,
• L4/Dw>0.08,
• wherein Dw is a diameter of the rolling elements.