The invention relates to a fluid dynamic bearing system particularly to rotatably support a spindle motor to drive the disk(s) of a hard disk drive. The bearing system comprises a bearing sleeve and a shaft accommodated in a bore in the bearing sleeve and rotatably supported with respect to the bearing sleeve, the surfaces of the bearing sleeve and of the shaft, which face each other and are separated by a bearing gap (3) filled with a bearing fluid, forming at least one first radial bearing region. According to the invention the diameter of the shaft is chosen such that the relationship between the bearing distance, i.e. the distance of the fixing point of the shaft to the first radial bearing region, and the diameter of the shaft is equal to or less than 0.9, and that the diameter of the shaft is preferably 3 mm to 5 mm.This provision causes the resonance frequency of the bearing to shift to a higher, uncritical frequency range.

 
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~ 00485