I'm considering a 26 or 28t granny gear for my Shimano 105 Crankset. The crank now has 50, 39 & 30t chainrings. I'm using a 105 triple front derailluer and an Ultegra GS rear derailluer.
I'm using a 10 speed chain.
The SG G-26 is the correct 74 BCD, but is discribed as a MTB chainring: http://cgi.ebay.com/Shimano-SG-G-26-...92346847569163