Originally Posted by
YogaKat
Something else I found was that if I changed gear on the rear and got some "crunching?" type noise that adjusting the front gear a bit seemed to bring it back to quiet. Am I doing this right?
Yes.
As you shift the rear, the chain moves inward and outward, which sometimes causes it to rub the front derailleur cage. When you adjust the front a bit to fix that, you are "trimming" the front. Good that you figured that out. If you glance down briefly at the chain and front derailleur you will see the chain rubbing one side of the FD cage.
I have seen some front derailleurs worn through from the chain being allowed to rub against it for miles & miles.