John G.wrote a question about Shimano Ultegra CS-6700 Cassette on August 17, 2011
I am running an Ultegra SL drivetrain (RD-6600G on the back, I believe) with a CS6600 11-25 on one wheel set and 11-23 on another. I would love to put a CS6700 11-28 on one but have heard/read that my rear derailleur can not handle the 28? Is this true? Do I have to hunt down a CS6600 12-27?