I upgraded my 8 speed to a 9 speed a few weeks ago.( new cassette, brifter and cable
) and the other day I shifted in to my 53 - 12 and it made a odd noise. I thought it was the deraller pully hitting the small cog, so i adjusted the screw on the back. Nothing, so I checked the limit screws again nothing. than I noticed the paint was missing from the weld on the chain stay. I shifted in to my small ring small cog no rub( chain line) but in my big ring rub city. any sugestions. PS the frame is aluminum.

could I some how spacer it?

thanks
Chris