I double shimmed last year and had no problems. The shims stayed in place ( double stick tape hold them in place). I did have to do a slight adjustment to the brakes. When I first put the shims (both pair) in place it was like having the brakes on already. You might have to have your LBS adjust them if you aren't familiar with how but other than that no problems. That was the only way I could get comfortable and be cofident I had control of the brakes/shifters.