Derailleur conversion
Hey so I recently upgraded to a mixture of Sram Force and Red componentry from my previous 105. It was well worth it. My brother just got a hold of a bike with low end SIS components. I want to put my old 105 gear on his new bike, but the issue that I'm running into is that my old front derailleur is 34.9 and his seat tube is a 31.8... I wanted to try and use a shim to make it work. Think it'll work?