PURPOSE: To reduce the resonance frequency of a handle bar and suppress the vibration of a car body transmitted to the handle bar so as to improve the driving sense, by contacting the fitting hole of the handle bar to a fork tube only at a part in the full length of the fitting hole.

CONSTITUTION: From the upper surface of a top bridge 3 in a front fork 1, the upper ends 2a in the left side and the right side fork tubes 2 are projected. While fitting holes at the bases 7 of a pair of left side and right side handle bars 6 are fitted to the upper ends 2a of the fork tubes 2, they are fixed by the fixing parts 12 of the bases 7. In such an installing structure, each fitting hole 11 is composed by providing a closely fitting part 11a fitting closely to the fork tube 2, and a playable fitting part 11b where the inner circumferential surface is not contacted to the fork tube 2. As a result, the fitting hole 11 is contacted to the fork tube 2 only at the closely fitting part 11a, so as to suppress the vibration of the car body transmitted to the handle bar 6.