A suspension element is disposed inside of a rim. The upper end of the suspension element is connected to a first support member mounted to a vehicle body. The lower end of the suspension element is connected to a second support member rotatably connected to the disk on the wheel. The shock and vibration from the wheel in the vertical direction are damped and absorbed by the suspension element. Also, a spring mechanism and a flat bearing are disposed in the wheel. The spring mechanism is disposed between a rotating member rotatably supported on the vehicle body and the rim of the wheel. If the rotating member is fixed to a brake drum, braking torque is transmitted to the wheel through the spring mechanism. The flat bearing is disposed between the rim and the rotating member and prohibits the axial movement of the wheel relative to the vehicle body.