The configuration object of the Timeline view can have various properties which you can use to configure your personal Timeline view.
I would advice you to look throw all of them in order to know how you can work with the Timeline method more correctly and comfortable: https://docs.dhtmlx.com/scheduler/api__scheduler_createtimelineview.html.
Answering your question I want to notice that you should use x_start, x_size and x_length properties.