Originally Posted by
up4speed
the noise I am referring to is the chain hitting the right side of the front derailleur when I am using the small chain ring in front and the small gear in the back.
That's what happens when you crosschain. Don't do it.
If your derailleurs are properly adjusted and working right, it WILL chain-rub when you crosschain (forcing the derailleurs and chain to operate in a non-optimal mode, i.e. OPERATOR ERROR).
It's not just your LBS mechanic insisting that you avoid crosschaining. Everyone else on this forum have been telling you that too.