No adjuster on this rear derailleur RD-M771

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Graham
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No adjuster on this rear derailleur RD-M771

Post by Graham »

Modern equipment - pah !

The ferrule just sits in the hole - with no adjustment. I've checked the techdocs and that is the way it is designed.

This only leaves a rather crude adjuster on the downtube thingy. The old seven speed STI shifters on the bars have no adjusters.

I can probably tolerate this setup, but is there some way to get a decent adjuster into the cable run ??

[Afterthought] If I revert to downtube shifters, there would be no easy adjustment unless I can find some way to add it . . ..

130401DerailleurNoAdjust.jpg

130401DerailleurNoAdjust2.jpg

130401DowntubeAdjust.jpg
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Mick F
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Re: No adjuster on this rear derailleur RD-M771

Post by Mick F »

Oh dear. Poor design.

First thought is of an adjuster from brake calipers. The unit has a lock ring. Fit one at the end of the cable outer, and adjust the length by moving the locknut.
Mick F. Cornwall
bumper
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Re: No adjuster on this rear derailleur RD-M771

Post by bumper »

There should be one where the cable enters rear derailleur on an XT. Has someone just jammed the ferrule into it?

My XT has a screw barrel adjuster there.

You could always add an inline brake cake adjuster if you have one.
Brucey
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Re: No adjuster on this rear derailleur RD-M771

Post by Brucey »

I daresay you can fit an inline adjuster in the cable outer run, or on the rear mech if you want to.

Some other DT cable stops have a proper barrel adjuster, maybe they would suit better.

Shimano designed the mech to be used with shifters that have a barrel adjuster in them. BTW, for years the typical MTB setup have had two, only one of which ever got used. The other one would seize up or get broken.

Techdoc here;

http://techdocs.shimano.com/media/techdocs/content/cycle/EV/bikecomponents/RD/EV-RD-M771-2706_v1_m56577569830625641.pdf

No barrel adjuster.

cheers
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~~~~~~~~~~~~~~~~~~~~~~Brucey~~~~~~~~~~~~~~~~~~~~~~~~
reohn2
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Re: No adjuster on this rear derailleur RD-M771

Post by reohn2 »

I have one of those d/tube adjusters and don't like it at all,you can replace with the screw/barrel type fitted to rear mechs or similar to the one on the other side(front mech adjuster) which is much better and doesn't get knocked out of adjustment when cleaning the bike etc.Yep a bad design :?
On the tandems I have inline adjusters similar to these:- http://www.sjscycles.co.uk/jagwire-in-l ... prod24781/
And these which fit into the STI spigot:- http://www.wiggle.co.uk/ritchey-cable-t ... hopping-au

I agree the rear mech should have an adjuster on but they are designed to be used with MTB pods which have the adjuster at that end.
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Graham
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Re: No adjuster on this rear derailleur RD-M771

Post by Graham »

Thanks very much, to all, for the speedy response.

It appears that this should be relatively easy to solve. It is very useful to have the recommendations and advice from others who have encountered an equivalent situation.

When I bought the derailleur ( secondhand, for a keen price ) I didn't even notice that there was no adjuster. I just assumed that every rear derailleur has one.
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meic
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Re: No adjuster on this rear derailleur RD-M771

Post by meic »

The downtube adjuster on my bike works just fine with my XT shadow derailleur.

It is as Reohn said one of the screw in barrel type. Or you can fit an inline one at the STI unit. Shimano do one that goes between the STI and the cable.

Though I dont know where you can buy them.
Yma o Hyd
GavinC
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Re: No adjuster on this rear derailleur RD-M771

Post by GavinC »

None of the Shimano Shadow rear mechs have a barrel adjuster - I guess they're rolling out this new 'feature' across all of their MTB rear mechs.

I fitted a Jagwire Rocket adjuster to my SLX Shadow rear mech - similar to the Ritchey one that Reohn2 mentioned. Its desgined to fit into an STI lever, but works just as well on a rear mech with no adjuster
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