Illustrator - How to export artboard in .ai format with only what's inside artboard

Question

I have a huge map made in Illustrator. I made 30 artboards in this map and would like to make an .ai file from each artboard in order to work with smaller files. But each time I save using .ai and chose "use artboard", every artboard is saved with every element of the original file and weights the same size.

How can I save artboard to .ai format with it's content only ?

Here's a screen cap to illustrate : black stroke box is the artboard I want to export in illustrator format without the elements outside it. I don't mean "hide' this elements but really remove them

Answer 1

Not possible. Either clean up the file manually or find another way to work with this large map.