I plan to put a compact crank on my bike and was wondering about the compatibility of my other components. Right now I have Shimano 105 ten speed all around. I've heard that my shifters will work with either a double or a triple setup. I assume that I will need a double front derailler but am not too sure about the rear derailler as it is a long cage for the triple. The crank is a Shimano R700 50/34 replacing a 105 50/39/30 (which will be installed on my commuter bike). I'd like to use the same bottom bracket if possible as well. Of course, I'll be installing a new chain at the same time.