Originally Posted by
RNAV
By design, the limit screws aren't supposed to move. There are different grades of locktite, with blue being the least powerful (and what I would recommend for this application). All the locktite is doing is ensuring that your limit screws function as designed, so no warranty voidage. Worst-case scenario, simply replace the limit screws and no one will know the difference.
I do like [MENTION=273237]oldnslow2[/MENTION]'s advice to mark the limit screws to see if they rotate. That would be a good way to diagnose the problem without using locktite. A simple black sharpie will work, just make sure you mark both the screw and the derailleur body. If they move, then you'll need to use locktite.
By the way, if I were you, I'd be pushing real hard for Sram to 1) permanently fix the problem, and 2) replace your crank arm under warranty if your crank arm has been scratched at all by the chain.
Sram has been very responsive. They called my LBS and said they will do "whatever it takes" to make things right. A Sram rep is going to visit the shop and personally check out my bike. When you drop close to 3 grand on a complete groupset, one would expect a good response from the manufacturer. And they have delivered.
There are some thoughts about the possibility of an incorrectly sized bottom bracket install, which was done by a different LBS that I do not frequent any longer. We'll see what happens!