Originally Posted by berner

I have two 1/2 degree shims under one cleat. I did this on my own because one knee was tending to brush the top tube. Obviously, that knee was not tracking straight up and down. That same knee occasionally experiences some discomfort, (mild pain). Additionally, I inserted an arch lift under the foot bed in the shoe. This mostly cured the inward flopping knee and reduced any discomfort to nearly zero. Just a few days ago, I carved away some of the foam under the foot bed and today the knee is complaining a bit. Whether a shim under the cleat is called for depends on what you may be experiencing. I believe you can experiment on your own with shims because it is easy to do or undo for minimal cost.