To have the various kinds of riding positions set by a driver by making a handle bar variable in height and width, which is provided for a motor bicycle and the like.

The height and width of a handle bar 46 adapted to a dummy motor bicycle is increased/decreased so as to be changed by side grooves 54a and 54b formed in hold parts 56a and 56b consisting of the handle bar 46, and also by sliding and dispacing hold parts 60a and 60b along the slide grooves 54a and 54b.