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New rear mech

I was going to convert to a 1x but decided against it for the time being,so I just want to upgrade my rear derailleur to a M591 Deore from a Acera M3000 but the cable adjuster is in a different location,will this effect my shifting as my cable runs along my chainstay?
Do I just need a longer rear cable?



  • JBAJBA Posts: 2,684
    Just fit a new cable when you swap the derailleur.
    “Life has been unfaithful
    And it all promised so so much”

    Giant Trance 2 27.5 2016 ¦ Bird Zero Mk1 ¦ Giant Revolt Advanced 2 2019 ¦ Giant Anthem 3 2015 ¦ Specialized Myka Comp FSR 2009
  • reaperactualreaperactual Posts: 751
    edited 13 January
    I'd always fit new cables as routine anyway but with the M3000 mech being low profile Shadow+ you won't need the cable to do a 180 degree loop back to reach the cable stop.

    Not having a loop back will slightly decrease shift lever effort and have a positive effect on shifting performance too.
  • whyamiherewhyamihere Posts: 7,365
    Hang on, are you changing from the Acera to the Deore? I know the Deore is a higher spec generally, but that's an old model, and the Acera has much more recent technology trickled down to it. Of the pair of them, I'd choose the Acera.
  • reaperactualreaperactual Posts: 751
    edited 13 January
    Very good point @whyamihere I'd seriously consider the Deore M592 a worthy upgrade to the Acera. Best of both tech in one unit.

  • Wow some valid points there guys,think I was a being a bit snobby :D as I know Deore to more of a mid range group set and I have just recently upgraded my chainset to SLX.
    As for the M592 it's a bit more expensive than the 591 but has sort of the same profile as the Acera.
    Good job lads more food for thought.
  • reaperactualreaperactual Posts: 751
    edited 13 January
    To be honest @karljeff72 I had a previous bike fitted with the same Acera rear mech and somehow one of the bushings around one of the pivot points snapped in two and fell out after 6 months use which turned the whole thing sloppy.

    Could have been an isolated incident or very rare but bought a new, unused 2nd hand Deore M592 mech on ebay for £20ish to replace it, great quality and is still on the bike now running well two years on so worth the extra cost imo. 👌
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