Dear all,
I have a novara Randonee touring bicycle. It's amazing but i'm looking into upgrading the rear derailleur/cassette to a more suitable derailleur/cassette for touring.

It comes with a shimano 105 long cage rear derailleur and a 11-28 9 speed SRAM cassette. I'm thinking about putting a shimano XT rear derailleur along with a 11-34 cassette. Any suggestions to which derailleur i should get and why? thank you

An XT will work fine with an 11-34 and any road shifter. You could down spec to a Deore if you want a less expensive alternative. Either will work.

+1 on the Deore. XT is nice, but the reliability and durability of the Deore is just as high for half the price. I spent around $50 on mine, and about $40 for my 11-32 SRAM PG970 cassette.

Alternative is to downsize your crank ring(s)

Here is an other vote for Deore or higher. My Deore rear derailler on my commuter is working just fine after 3.5 years of year round commuting the Buffalo "rust belt". I am amazed that with all the nasty road slop that gets on the rear derailler throughout the winter months of riding that I have had absolutely no problems with the rear derailler.

Happy riding,
André

i had a look at the Shimano XT M772 shadow, it looks interesting with that new shadow feature. is it any good? has anyone tried it, and found it worthwhile? or should i just go for a regular deore derailleur? thanks

The Shadow series just brings the cage and body in closer to the wheel and tighter to the stay for off road obstacle avoidance. Not necessary on a touring rig unless you're touring backcountry trails where it might get snagged.

I haven't tried the Shadow but I can see the appeal for off-road use. It might even shift a little quicker. As long as it is high-normal, I don't see any issues with it. Probably not even any issues with low-normal but I'm not a fan of those. The price is right for either. I've Shadow XT and non-Shadow at Icyclesusa for around $55. That's dirt cheap for an XT.

The going theory on low-normal derailleurs, aside from if you snap a cable you still have a useable gear, is this:

The spring tension is pulling to the big cogs, and shifting off-road (or under touring load) to an easier gear will be improved. Faster downshifting means less time on the hills "easing up" on your pedal stroke to change gears.

I've had the early low-normal (XTR) and never found that to be the case. The derailer hesitated during downshifts under load just like a front derailer will hesitate...and sometimes not shift...when shifting to the lowest range. To downshift under pressure, you are relying on the spring to move the derailer to the lower gear while in a high normal derailer you are dragging the chain up onto the larger diameter cog. You can put as much pressure on the cable as you like to make it shift. You can't put pressure on the spring to force it to shift. Essentially you have to wait until you ease off on pedal pressure...which will happen sooner or later.

Low-normal (formerly Rapid Rise) is a pig in a poke.

Deore is not as good as XT under adverse conditions -- which you WILL encounter touring. On a commute home one day, I was forced to ride through floodwater up to my BB; the front disc howled for two days, my socks bled onto my feet... and my Deore derailleur quit the next day. It was 2 months old. Never again. (I'd ride the floodwater again, it was fun; but no more Deore!)

Absolutely reliable shifting could be had with SRAM's X.4/5/7/9/0 mt. triggers and derailleurs, but would be a "creative endeavour" for your application.

You have 48/36/26 cranks, right? Be sure to get the cage size that Shimano refers to as SGS. That's because:

(48+34) - (26+11) = 82 - 37 = 45 teeth. An SGS derailleur will take up 45 teeth worth of slack.

Alternatively, you could buy a set of 44/32/22 rings. Those would give you lower gearing, and you probably could retain your current derailleur.

And fwiw, I'm liking the SLX derailleurs these days. SLX bits usually come in at a good price-point. They seem good value for the money.

Jonathan, yes i do have the 48 and i love them to be honest, they are very comfortable. I don't get where the 37 came from, and by SGS do u mean the short cage or the long cage... it is a bit confusing i'm sorry. But thanks for the tip, it's amazing, i'm considering the SLX as well.

What about the cassette, should i go for an XT as well or are the SRAM cassettes more reliable, my current cassette is an SRAM, thanks

The 37 came from your small chainring's 26 teeth plus your small cog's 11 teeth. The least number of teeth you can use at any one moment is 11 for the rear cog + 26 for the small ring, or 37 teeth. Your chain needs to enough extra links though, to accommodate the 34-tooth cog + 48-tooth ring. The derailleur needs to be able to extend to "soak up" those extra links.

By SGS, I mean long cage. I believe that SGS is an abbreviation for something; I forget what.

As far as choosing between SRAM and Shimano cassettes, I personally do not have much in the way of a preference between the two brands. Both are good.