You won't lose anything by unbolting the r der and giving it a good scrub with your favorite light degreaser. The pivots might be gritty and could use some lube. If you do the F der, mark the position on the seat tube with some tape so you know where it was set. F der position is easy to get wrong, but a few checks and some fiddling will get it where it needs to be. I'm not sure you mentioned what the drivetrain consists of in your posts.