Hello and welcome to androidforums. As for your question, you need to sbf back to stock. However I recommend reading as much as possible before you start doing any flashing. Anyways, to start, go here:
[GUIDE] Flash SBF to Motorola Atrix 4G - xda-developers
I use the 1.26 file to go back to square one, then up from there (doing update after update). You may be able to use the 4.1.83 sbf but I could not find the file. Also it takes 10-15 minutes for the entire process, so start it and walk away, there are time where your phone looks like it is frozen, just leave it, you will have a lot less stress if you do.