1x10 setup - do I need medium or short cage?

coursemyhorse

Hi guys, I have some questions and was wondering if you can help me.

I want to convert my Specialized Stumpjumper Comp 2007 to a 1x10 setup because I just love them. However...

1: Can I run a short cage rear derailleur on my bike with 1x10 setup or not? I would be running either a 32 or 33 front chain ring, and definitely an 11x36 cassette. I know I need to account for the full suspension travel and chain growth. Will short be too short or fine?

2: I know I cannot mix front shifter and rear derailleur. I wanted to use a Shimano XT shifter, but I noticed that the XT rear Derailleurs do not come with any short cages. Only medium or long on XT. Is that right? If that is the case, I do not mind running SRAM X9 rear derailleurs but....my next question....

3: What is the difference between SRAM X9 shifters and Shimano XT? I am sure I have read somewhere that XT have something that is better than X9? Is it to do with pushing through more gears at once? Do they work the same? Is it just feel?


Thanks guys

supersonic

1) Depends on the capacity of the rear mech and the total teeth difference of the cassette you are using. Short should be fine in most cases, even with an 11-36 ie capacity of 25

2) Front shifter has nothing to do with the rear derailer - rear shifter does ;-). XT medium would be fine but...

3) XT 10 speed rear mech MUST be matched with Shimano 10 speed shifters. In my opinion the Shimano XT is better made than SRAM X9, you can push and pull the bottom lever, and multiple shift with the bottom lever (down shifts). The upshifts work the same on both. Feel is a bit different, XT feels lighter and smoother.

coursemyhorse

Sorry I meant that I know the REAR shifter cannot be mixed with a different brand rear derailleur. Not sure why I said front. Thanks supersonic. So where do I look for this "capactiy" of the rear derailleur? Most just give a minimum and maximum tooth size and not this "capacity" range of largest minus smallest you talk of.

So why do the Shimano rear mechs not come with any short cages in XT? Bit rubbish isn't it? Is there no decent shortcage rear derailleur in Shimano? Any XTR short cage?

Am I obsessing over nothing with regard to small vs medium cage length on the rear derailleur?

EDIT: Just read up and realised that the SRAM X9 shifters cannot be used with finger pull back to upshift. For that reason I can't use them as would want that.

nicklouse

It depends on which XT kit you look at new 10spd or the 9spd. And just to say it again 10 & 9spd kit is not mixable.

Have a look in the FAQs for some range info. Or look at the manual forwhatyou are looking at as that will have the info.

coursemyhorse

10 speed is what I am after. I see none available with "short" cage, only medium.

coursemyhorse

Although I just noticed there is the Shimano Saint m810 9spd which has short cage. I know I said I want 10spd but just out of interest, this states compatible with up to 11-34 tooth cassette. is it not possible to run 11-36 with it?
Also can someone explain to me difference between GS and SS rear derailleurs?

.blitz

Take it easy with a short cage mech on a FS bike.

The amount of suspension movement and the path it takes can have a big effect. Remove the shock and watch what happens to the mech as you change gear. Although it's possible to lengthen the chain it might be dragging on the floor in the higher gears.

FWIW I have a long travel 1x9 FS with 36T chain ring, an 11-28 cassette and a short cage X7 mech. An 11-34 cassette at full compression would bust the mech.

Anonymous

I've read that SRAM mechs have different lengths to Shimano, e.g. one brand's "short" is another's "medium".

Don't know if that's true.

Anyway, need to do similar myself for a possible 1x10 set up, but this is on a hard tail. Advice was to go medium or short and along with a single speed chainring up front shorten the chain slightly to further reduce the risk of chain drops. Again, not sure if this is correct but sounds logical. Planning for an 11-36 or 12-36 with 34t up front.

And yeah, I'd also read that FS should stick to medium and allow some slack for the suspension. Might be better to go with a chain device in that case.

supersonic

The nominal wording is only a vague indicator of capacity: you must always look up capacity if in doubt. Even the same brands mechs have different capacities even though they may be labelled similarly!

RE suspension: if you measure the chain with the sus at the point of maximum effective chainstay length, you will not rip the mech off. As Blitz says, the only consequence now if capacity is exceeded in the lowest capacity combo is slack in the chain. Generally sus will only extend the chain length by a few mm, but it can be more, equivelent to 2 or 3 chain links or capacity units.

Always measure the chain length using the big/big method, add two links, and for full sus measure at that pint of max extension. If in doubt about capacity, go for a longer mech.

coursemyhorse

Thanks for all your help with this guys. I have a sort of obsession with using a short cage because I like the fact it has higher ground clearance, looks neater and I assume offers less tendency for chain slap as a shorter chain length can be used? To be honest, I think none of this matters because I want to use shifters that have index finger pull to upshift, which I think only Shimano do? I really want multi and instant release too. Just reassure me, there is no normal style thumb/index finger shiter SRAM offers that does this is there?

Chunkers1980

Re chain slap - shorter the cage the closer to the stay the chain will be, so from that persepective more likely!

coursemyhorse

Now to completely confuse me, I have just read on another forum it is possible to mix Shimano and SRAM shifter/rear mechs in certain combinations. i.e. Possible to run XTR rear shifter 10 speed, SRAM X9 9 speed rear mech, Shimano 10spd cassette and it all work hunky dory. Hmm.

"Originally Posted by g3rG
Yes.

Since last November I have been using a Shimano 10-sp front shifter with a Sram 9-sp RD, a Shimano 10-sp cassette, and a Sram 10-sp chain. It works because the full pull of the new Shimano 10-sp stuff is exactly the same as the full pull of the old Sram 9-sp stuff. The Shimano incompatibility engineers must have screwed up.

Shifting has been perfect, even when I screw up and shift under load. I do a lot of steep climbing, so the system has had some abuse. Since the install I haven't even had to adjust it.

gerG"

"Yes g3rg. Yesterday I made some tests (in bike stand only) an this are the results:
xtr 980 10V Shifter + X9 '09 9V rd + 10V cs81-10 = OK
xtr 980 10V Shifter + SLX 9V rd + 10V cs81-10 = NOK (as expected)
X9 '09 9V Shifter + XT 773 10V rd + 9V cs770-9 = OK
X9 '09 9V Shifter + SLX 9V rd + 9V cs770-9 = NOK (as expected too)

Some remarks:
X9 rd needs a little bit longer cable lenght than shadows (dynasys or not). It's necessary to change the shifter cable to try this;
3x10 dynasys with 11-36 cogset needs long cage rd. My X9 rd is medium and the chain was too loose in granny;
It's necessary adjusts in h/l screws in rd and in shifter barrel to tune. This tune sounds harder for me. "

supersonic

Don't do it. I have tried them ALL, and if you want it to work properly and consistently, stick to the right stuff.

The cable pull changes through the gears too, the architecture is built onto the mechs to compensate. Some gears will just not work right.

coursemyhorse

Why do several people confirm this works supersonic do you think? Everywhere I read I admit, I have had it drilled into me not to mix. I found it interesting.

supersonic

Didn't work for me! Not reliably. I tested over 50 parts over the summer!

coursemyhorse

I notice it seems to be Dynasis only, with "the older SRAM 9 spd stuff". So maybe the combination was not quite right. I don't know. Seems hassle to mix.

supersonic

There are bodges like running the cable into the stops differently, but I wouldn't bother! Shimano is cheaper and works better IMHO, so I'd just go with that ;-)