So, it was brilliant to get out for a post-work ride but not so great snapping my rear mech 😥

Anyway, I’m looking to replace like with like, but I don’t know whether I have a GS or a SGS cage on the bike.

I’ve got hold of the manual and it looks like I can run either but I’m not entirely sure.

The bike’s one of these
http://www.canyon.com/_uk/mountainbikes/bike.html?b=2558

and this is the manual for the mech
http://media.canyon.com/download/manuals/Manual_RD_M_773_EN.pdf

Could someone please help out a dimwit?

RT,

As a rule of thumb:

3x Chainrings = SGS Long Cage for up to 45T range.

2x Chainrings = GS Medium Cage for up to 35T range.

Your link to the bike shows a triple, so I would get the SGS version.
You can change rear mechs without altering the chainlength.

PaulD

although to be fair 9 times out of 10 a GS is fine, just don’t use the extreme gears, ie big chainring, big sprocket and little little, and you will never have a problem.

I have always used GS rear mechs on my triple set ups, gets the mech up out the way that little bit more.

So can a GS mech not be run with a 36t rear 10sp cassette if being part of a single/double chain set?

Single it can, double possibly but getting it to work in big big is likely to mean too much chain slack in little little.

So can a GS mech not be run with a 36t rear 10sp cassette if being part of a single/double chain set?

I use the above on a double chainset no problems.

Suspected as much. I have a mid cage on my 34t 9 speed cassette so assumed there would not be too much difference…

By choice, I always use short cage rear mechs and triple chainsets on my bikes, with no issues whatsoever. I do have a long cage XT RD-M761 on my ‘main’ mountain bike with a 44/32/22 chainset, but only because that’s what came on it (emergency eBay purchase after my pride and joy was nicked), when/if it dies it’ll be getting replaced with a short cage equivalent. I run a short cage XT RD-M732 with a 46/36/26 chainset on my commuter bike and it’s never been anything less than perfect.

So a GS M780 rear mech will be fine on a double 26/38 with an 11-36 cassette?

So a GS M780 rear mech will be fine on a double 26/38 with an 11-36 cassette?

When the XT/SLX Shadow Plus mechs are available that’s the combo I’m hoping to switch to, so it would be great to have confirmation from anyone using this. Nominally the GS has a 35T capacity and this set up is 37T difference. I feel a GS might be pushing it a bit, especially as on this double set-up I’d want to actually use big/big and it would be on a full-suss which will add some chain growth.