Going from triple to double
I have read that my shimano 105 front shifter will work with either a triple setup or a double. My bike currently has a triple, but I have bought a double crank, bb, and new front and rear derailleurs. Once I install my new parts how do I set up the front shifter for a double?
Actually you set it up the same as you would for a triple.
Go to http://www.parktool.com for detailed instructions. Do each step in proper sequence leaving nothing out. The Shimano instructions are also available online.
No need to do anything to the shifter itself. The limit on the ft der will keep you from moving the shifter to the 3rd indexed position. As long as limits and cable tension are set correctly.