What is a Shadow derailler?

[scotsbikester]

Sorry if ive started something with my question. It's not a big issue whether it works or not really, I'm just the kind of bloke who needs to know how stuff works!
My understanding of things is that all the "work", if you like, is done at the shifter and the dérailleurs job is to push backwards and outwards when it's told to. My thinking is that it should work fine if the shifters a nine and the cassette is too. As long as the throw of the mech can cover the width of the cassette there should be no problem, although there seems to be a lot less backwards motion than on a conventional mech.
I think that my original question has been answered by @scotsbikester in that it's the mount that makes it different.

I think the mount is one difference, and the stickyoutness (technical term) is another.

As far as I can tell, the stickyoutness, or rather lack of, is to stop the derailleur catching on undergrowth/rocks/tree stumps or whatever else mountain bikers might catch the derailleur on. Doesn't make any difference to me, as my M772 (which is a Shadow) is on a road bike.

The point of the direct mount, again as far as I can tell, is to make the derailleur firmer, so that on bumpy rides the chain doesn't flop about as much.

The reason I got an M772 (actually, I have several) was because they have a very good reputation for longevity, especially due to a lack of a top pivot, which tends to wear on non-Shadow derailleurs. Or something.

 

[Ajax Bay]

the kind of bloke who needs to know how stuff works!
My understanding of things is that all the "work", if you like, is done at the shifter and the dérailleurs job is to push backwards and outwards when it's told to. My thinking is that it should work fine if the shifters a nine and the cassette is too. As long as the throw of the mech can cover the width of the cassette there should be no problem,

I commend the article written by the late Sheldon Brown, to augment your understanding (not Shadow specific).
https://sheldonbrown.com/speeds.html
The essential drive train differences between the speeds include: number of sprockets, sprocket pitch, shift ratio, cable pull, number of clicks (in indexed shifter).
Relja explains it well too: https://bike.bikegremlin.com/1278/bicycle-rear-derailleur-compatibility/
Isn't the primary feature of 'Shadow' RDs that they have a narrower profile? (Repeating what @scragend send v early on.) Here's a quote: "with Shadow technology. . . the mech has a much narrower profile, with the parallelogram sticking out far less and sitting inboard of the rear dropout, so there’s a lot less chance of it being ripped off if you get a little too close to a rock or other trail obstacle."
Diagram here: https://bike.shimano.com/en-EU/technologies/component/details/shimano-shadow-rd.html

 

[I like Skol]

I commend the article written by the late Sheldon Brown, to augment your understanding (not Shadow specific).
https://sheldonbrown.com/speeds.html
The essential drive train differences between the speeds include: number of sprockets, sprocket pitch, shift ratio, cable pull, number of clicks (in indexed shifter).
Relja explains it well too: https://bike.bikegremlin.com/1278/bicycle-rear-derailleur-compatibility/
Isn't the primary feature of 'Shadow' RDs that they have a narrower profile? Here's a quote: "with Shadow technology. . . the mech has a much narrower profile, with the parallelogram sticking out far less and sitting inboard of the rear dropout, so there’s a lot less chance of it being ripped off if you get a little too close to a rock or other trail obstacle."
Diagram here: https://bike.shimano.com/en-EU/technologies/component/details/shimano-shadow-rd.html

Funnily enough, if I ever want to search about cable pull ratios and groupset compatibility i always start my research at the Sheldon Brown website

 

[Jody]

The point of the direct mount, again as far as I can tell, is to make the derailleur firmer, so that on bumpy rides the chain doesn't flop about as much.

That's what the clutch is for.

I would have thought direct mount aids more precise shifting as there is less play from worn pivots.

 

[Jameshow]

That's what the clutch is for.

I would have thought direct mount aids more precise shifting as there is less play from worn pivots.

Still got the same number of pivots?🤔
Is it not just an extended derailleur to handle bigger cassettes?

 

[Jody]

Still got the same number of pivots?🤔
Is it not just an extended derailleur to handle bigger cassettes?

It's my wording. The B link is removed and that increases stiffness because there aren't two pieces bolted together. Not a pivot per se but an extra bolt/link that doesn't need to be there.

It's apparently to do with the ease of wheel removal rather than cassette size.

 

[Greasy Gilbert]

Just an update, after fair bit of tinkering and cussing I can confirm that it now works fine with a 9 speed (32/12) cassette and 9 speed Deore Shifter. I hope this may of of use to someone and thanks to those who've taken an interest.