M771 or M772 (non-shadow vs shadow)
Can't really tell the difference having fitted both in the last year (as well as an SLX - all on various bikes) - I guess the shadow version is a bit ligter and cable entry better but worth replacing a part worn m771 for an m772?
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Just my experience and opinion but I would run away from any mech. that has Shadow in its title.
Setting it up and adjusting it correctly became a week long activity and even then I didn't manage it and the pivot wore out incredibly quickly.
It was replaced with a non shadow version. Straight on and set up perfectly in 15 minutes and works like a dream 500 or so miles later.
I'll not have Shadow ever again.
Just looking at it up there is giving me anxiety issues.
My SLX has been fine but I got an old m772 which is skipping like mad as I bashed it ages ago and replaced it with an SLX - I have a M771 from my old bike which worked fine so I think I'll just stick that on and bin the M772 (after taking spares off it 😉 )
I've XT Shadow on one bike and Saint Shadow on another. My partner also has XT and SLX Shadow on her bikes; I've installed four or five others; and I've retuned a couple on the trail for other riders. I can't say that they're any different to set up than the traditional design; so, aprt from making sure that the little nub on the mounting plate is correctly positioned - something which is clearly noted in the Shimano instruction - I've no idea why anyone would have difficulty which was specifically related to the Shadow design.
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