Originally Posted by
Bike Gremlin
However retrogrouch this may sound, most changes are for the money making - marketing reasons. "Added value" if you like.
One of the things I like about triples is the ability to use dirt cheap 7 speed cassettes and chains, along with friction shifting. I use it every day, not just "for touring". Dirt cheap AND robust.
For the OP - the setup should work fine.
Largest rear sprocket?
I've used Shimano Sora and Claris with as big as 34 teeth (I think factory recommendation is 32 max). Sora was SS (short cage) at that - lacked on the chain wrap capacity, had to stay away from the small-small combos (which should always be the case anyway), while Claris one worked with no problems. They are both compatible with the pre-Tiagra 4700 10 speed Shimano shifters/derailleurs. For the same (pre 4700 era), you could use any Shimano MTB RD, that is for 9, or fewer speeds (10 and 11 speed ones have different cable pull standards).
The frame I'm building up is a Surly Disk Trucker, so anything lower than a 9-speed would be an injustice in my opinion. I'd like to put a Rohloff on it, but I got this bike cheap, and I'll ride it a while and then flip it. I contacted RaceFace to see if they can advise me on what to get. They do still make triples as far as I know. If I can get a decent triple crankset and Brevenalle shifters, then I think the rest will fall into line.