Help with System Reserved Partition

[granets]

Hello LTT 

I had to reinstall my pc that had Windows 8.1 but had a weird problem - I had an error saying there is not enough space on my system partition to install windows. Note that I just formatted my Windows parition and it had 129GB of free space. My system reserved partition had 14Mb free from 350. So I popped in my windows 7 CD, - same problem, it will not install. So I took the risk - I deleted my Windows partition and extended the System reserved partition to the free space. Now I have a 130GB Windows drive. I started the installation of Windows 7 on the new partition, hoping my 1.8TB of Data drive will survive. And to my surprise - it did. But now I face a problem - next time I need to reinstall my windows and I format my Windows partition, what do you think will happen? I fear I will lose all my data.

My question is - can I split off my system reserved partition again? 

Or am I in the clear, windows somehow moved the files, and when I format, all should be good? 

I really don't want to copy over nearly 2TB of data, and I don't even have a spare drive. Please, I need help.