How do i fix a file where relinking or updating file is too slow and generating 60+MB pdf from a 4mb Indesign file?

Question

I have an 18 page files linking several pdf images and working with this file is horribly slow.  These pdf images(total of 15) easily take a min to relink or update (pdf's are at max 2mb but majority are less than 1mb).  The Indesign file is only 4mb but when i export or print to pdf I get a 60-70mb file. Exporting or printing these 18 pages easily takes 30 min.  I can't use the file with a higher display quality unless i have the patience of watching a plant grow on that day. I've read a majority of ways why InDesign would be slow. At work im operating Windows 7, Indesign 6 and I have 32MB of RAM.  Extremely frustrating and reminding me of the days of dial up internet.  I've already done a SAVE AS and tried to reduce linked files image size and to no avail has not helped.  I was able to get my 72mb pdf file to reduce to 6mb after using Adobe Acrobat and getting rid of the hidden information but I lose alot of quality in the linework.  I am guessing its because these pdfs are generated from Revit or Autocad is why it might be holding onto some hidden info. So how do i make this file work faster (relink,export,pdf etc)?

Answer 1

Just to note as well, InDesign only links to files, there's no embedding, you would see a 4mb file, but if it's linked to a 10mb pdf and it has to include all that PDF in the final file then it will be circa 14mb file.
What you have is a vector heavy PDF and there's no real way to reduce that without losing quality.
You may have better joy by opening the linked PDFS in acrobat and using File>Print and choose Adobe PDF (or another method) to basically refry the CAD pdfs.
I'd do this with a copy of all the files though just in case something goes drastically wrong.
Frankly, I feel it's the nature of how CAD pdfs are made that's causing the downfall here, refrying these and Printing these files to PDF removes a lot of the complicated things happening in CAD files and makes a very dulled down PDF version.
Once you've done this then try FIle>Export from indesign to make your pdf.