What are you trying to solve?
Any consumer acid (vinegar, ospho, lemon juice, etc) won't hurt titanium, but then, titanium doesn't get anything on it that needs acid to remove. If you're trying to remove lube from the internals, that's mechanical with q-tips, etc.
If you're talking Atomic regulators, the spring, piston, etc. are not titanium, and vinegar is fine.
If you're O2 cleaning it, a solution of blue-gold does that without acid.
So I wash mine in an ultrasonic cleaner with blue-gold to O2 clean them. I don't bother with acid. That's for brass and green verdigris.