Originally Posted by Steve B.

I would just use any Shimano road cassette - 12-25, 11-25, 11-28, whatever. Might need a B screw adjustment for snappier shifting. If you think about the fact that many of the cogs in an 11-34 cassette are already used in a tighter cassette, the system will still shift. It's not like going the other way and trying an 11-34 on a system - chain length and rear derailer capacity designed for a road cassette.