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Shimano DM derailleur, yet another failed standard?

Udi

RM Chief Ornithologist
Mar 14, 2005
4,915
1,200
Just tried to mount my new Shimano DM setup, but various shadow mechs use completely different link widths and thread sizes so it seems you would need a different hanger depending on the vintage of your modern Shimano mech (and its correlating retarded "B2" link, which the DM standard was supposed to get rid of).

In my case I have a hanger that will fit my 10spd shadow (clutch) Saint but not my 10spd shadow XTR. Given the Saint weighs approximately 300kg I'd prefer to keep it for anchoring my cruise ship, which it does very well.

I have just finished weeding Shimano brakes off all my bikes - unfortunately I still like their drivetrains, but are the Japanese engineers just sitting around in their sailor moon pyjamas watching anime these days?
 
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Dogboy

Turbo Monkey
Apr 12, 2004
3,208
581
Durham, NC
The XTR Shadow + (+ being a clutch-type derailleur) was introduced before the DM standard, so yeah, some aren't compatible. Kind of a weird thing to be miffed about.
 

Bikael Molton

goofy for life
Jun 9, 2003
4,010
1,143
El Lay
Many (most?) other standards are different between the XC Race category (XTR) and the DH Category (Saint), so not sure why derailleur mounts would need to be identical. Pretty sure the direct mount XTR front derailleur wouldn't fit on yer DH bike either.

Also, ditching Shimano brakes is weird man; you might want to rethink that.
 

Udi

RM Chief Ornithologist
Mar 14, 2005
4,915
1,200
so much trouble for saving a few grams. :)
It's not really for the grams, it's moreso to get rid of the link which a) doesn't need to be there, and b) isn't particularly strong. It's not a huge bother, just a superfluous part of the design that would be nice to get rid of.

Many (most?) other standards are different between the XC Race category (XTR) and the DH Category (Saint), so not sure why derailleur mounts would need to be identical. Pretty sure the direct mount XTR front derailleur wouldn't fit on yer DH bike either.

Also, ditching Shimano brakes is weird man; you might want to rethink that.
The change to 10mm DM was across-board so it's not different between *current* XC and DH lines - just mildly annoying to owners of slightly older Shadow mechs as Dogboy pointed out.

As for the brakes, no thanks. I've used Shimano exclusively for many years (including their current gear) and have personally experienced the decline in quality and reliability each update. I think currently their reputation exceeds the standard of their actual product by a long shot, I just hope they don't hang onto that.

I still rate the cranksets highly (and select other lines - Saint shifters for example are really nice, while XTR have gaps in the casing and flimsy mounts to the bar), but while everything has improved from a functionality standpoint (thumb shifting, higher power brakes, servo wave, icetech - all good things), quality has dropped. I have seen numerous brake failures here, and derailleurs develop play much faster than the XTR M952 / DA 7800 days. Having said that they're probably more on par with SRAM now than actually inferior, but it's still a shame.

As for your XC Race / DH argument, I think differentiating those two lets Shimano down - primarily because they blindly assume that the heavy use market does not care about weight, and thus you end up with the 290-300g Shimano Saint/Zee clutch derailleur - and no short cage options in the XT/XTR range. What is more ludicrous is that sponsored pros actually get given shortcage XTR, illustrating the need without acting on it for consumers.

SRAM on the other hand have a superior methodology whereby the high end line was always stronger AND lighter, so if you spent the money on X0 you could have a 200g mech that would last a few seasons of DH. I prefer the Shimano shifters so for the last few bikes I've just built my own shortcage XTR mechs, but I think they could learn a thing or two from the competition and pick their game back up to their old (class-leading) standards.
 

Muddy

ancient crusty bog dude
Jul 7, 2013
2,032
907
Free Soda Refills at Fuddruckers
Interesting points Udi, I will still prefer Shimano over SRAM just because of the largess presented by SRAM. Having an enormous facilitation of products is not a bad thing, RS/SRAM/Truvativ are too tightly knit to have them stand alone in frame-ups. Kinda left in a daze actually having seen Gwin running FOX w/ SRAM drivetrains this year. It's all in the details in the end though, but committing to all or part of the SRAM family is a choice which gets made daily.

Individually aside SRAM would be left shifting uneasily on their feet if not giving us options to the minutia level to satisfy the masses. Shimano has the recognition of sustaining itself as the only other true drivetrain producer still, unless Sugino re-emerges in the next five years. Keeping some range limited keeps some level of commitment to the brand, and also a failsafe to the wash of trends.

As things stand, I am not going any further with cassette helper gears, anything like it. Switching out one season 13-39 nine speed to a 12-25 Dura Ace & 2x in the front. More range (offered) and better application. Period. Shimano likely knows this and is just charting it's course for the long run. e.thirteen tossing some chips on the table was hideous, HOPE gets the nod for just making the one. Shimano should let the XTR lineup have all cages be fit somehow, but I'd take SAINT even with another 50g slathered on it.
 

Sam B

Monkey
Nov 25, 2001
280
0
Cascadia
Getting rid of the B Link was intended to make shifting crisper, blah blah blah... but I have found that it's usually the part that bends (unless you have a really wimpy derailleur hanger). Without the B Link I have seen multiple fully broken derailleurs, versus the bent B Link that was easily straightened or replaced. Great idea to get rid of a pointless fastener in the Shimano derailleur, but it creates other problems...
 

bismojo

Monkey
May 5, 2009
271
39
That's one fancy chain tensioner!
thanks.. just wish shimano update their alfine chain tensioner with clutch (saint-grade, not zee-grade) mechanism, or create something useful (hollow-rad cage, ice-tech hose, 160/83mm XT cranks) instead of making DM standard, i thought centerlock and rapid-rise gave enough negative feedback for their R&D :D

Too heavy for SS :)

Look into eccentric bb
nice EBB.. but it's not an hardtail.. 8" bike with plenty of rearward shimz, DM mount and NW ring..

but if it is, you can always half-link it.. or get chameleon.5 with built in phil wood :P
 

CBJ

year old fart
Mar 19, 2002
12,861
4,156
Copenhagen, Denmark
I have it on my GT Sensor and I like it. It also makes taking the wheel in and out much easier (I transport the bike in my trunk so a huge help) and is claimed to give better shifting because it stiffer.

I got a 2015 XTR 11sp derailleur at home ready to get installed. I am looking forward to seeing how it will work out with the DM setup.
 

slyfink

Turbo Monkey
Sep 16, 2008
9,288
5,028
Ottawa, Canada
I've been running it for a year on my Mojo HD with a medium cage SLX. Maybe it was placebo, but I felt I noticed the change in crispness when running through the full cassette. It also seems tough enough to last a full year, but bent out of the way nicely when I fell on a rock, without causing any damage to the derailleur. I'm happy with it.
 

Udi

RM Chief Ornithologist
Mar 14, 2005
4,915
1,200
Hey Udi,
How do you go about converting an XTR to short cage? That's pretty cool!
It's really easy, you can literally bolt the short cages onto them, it's just a matter of knowing which Saint model is compatible with each XTR model.

The XTR (shadow) models will be M972, M981 and M985, while the suitable Saint models are M810 and M820.

The compatibility is essentially shadow with shadow, shadow-clutch with shadow-clutch, irrespective of 9spd/10spd. So the M810 cage fits the M972 and M981, while the M985 will need the cage off the M820.

You can buy the cages if you have a good Shimano part supplier, or just rob old mechs for them.
 
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4130biker

PM me about Tantrum Cycles!
May 24, 2007
3,882
447
That's awesome- I had no clue about the compatability- thanks!

I actually tinkered with an old XT, sectioning the cage, but promptly destroyed it by attempting to weld whatever seemingly un-weld able alloy they forge those cages with.
 
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DhDork

Monkey
Mar 30, 2007
352
0
Hell, AZ
It's really easy, you can literally bolt the short cages onto them, it's just a matter of knowing which Saint model is compatible with each XTR model...
Udi, any idea if this will also work with an XT mech? Have an XT on the hardtail now, and would be nice to convert it to a short cage.
 

troy

Turbo Monkey
Dec 3, 2008
1,006
739
@Udi I checked my shimano docs and Saint/Zee DM hangers have different dimensions than XT/SLX/XTR hangers as well (axle/pivot distance and angle) that is why You XTR der is so close to CS.

That's awesome- I had no clue about the compatability- thanks!

I actually tinkered with an old XT, sectioning the cage, but promptly destroyed it by attempting to weld whatever seemingly un-weld able alloy they forge those cages with.
You may find it useful: http://www.ridemonkey.com/threads/converting-xt-slx-shadow-mechs-to-short-cage.229145/