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  1. #1
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    6870 Di2 shifting issue

    No shifting issues with this bike for the past year until the last few weeks. The problem is there is some hesitation when shifting from the 3 biggest cogs each step down to the next smallest cog. Wont shift down unless i click twice but then it goes down 2 cogs. No problems with the other cogs. Only occurs while riding. Shifts fine in the workstand.

    Occurs regardless if in big or small ring.
    All other shifting is normal.
    Wheels are in proper position, even tried other wheels with same issue.
    Derailleur hanger is straight, even tried 2 other brand new ones , same issue.
    No crashes.
    Chain is proper length and not old worn.
    No drivetrain noise while riding.
    Tried microadjusting, didnt help.

    Any thoughts?

  2. #2
    RoadBikeReview Member
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    What is the condition of the chain and/or cassette? It is also possible that the derailleur itself is slightly bent.

    If it were my bike. I would try micro adjusting on the bike in the gears that are giving me trouble. If it shifts perfectly in the stand, there is no point in trying to adjust it under those conditions.

  3. #3
    'brifter' is a lame word.
    Reputation: cxwrench's Avatar
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    Your problem pretty much says 'derailleur hanger'. If the shifting is worst in the largest cogs that's your clue. Add some chain/cog wear and it's a high probability this is the problem. Doesn't matter if you've tried new hangers, they need to be aligned to the individual frame. The derailleur moves the chain horizontally between the cogs, the only way it can be worse at one side of the cassette vs the other is if the hanger is bent.
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  4. #4
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    Could try to clean and lube the pivot points on the DR - but that would be more likely to be a problem at the other end of the cassette.
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  5. #5
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    This. OP how did you verify the hanger is straight? With a alignment tool? Or eyeball?

    I recently swapped derailleurs on one of my bikes and even though it was straight previously (confirmed with a Park Tool DAG 2.2) the hanger was slightly out of alignment after a couple of years of moderate riding (about 1800-ish miles on it). Reused the same chain and cassette with the same amount of miles on it. Still shifts flawlessly back there (new derailleurs put on are Di2 for reference). But I'm probably due to replace the chain on this bike by the end of this riding season as it is showing signs of stretching when I measured it last month but still within tolerable limits.

  6. #6
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    I would normally say hanger alignment too, but I just had a similar glitch with a perfectly aligned 9070 Rd that had me stumped for a bit. Turns out some sticky road crud plus old lube gummed up the pivot point between the cage and body causing the cage to not pivot freely. It will result in hesitation like this. So yes, please check alignment with a proper alignment tool, but make sure pivot on Rd is free.

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  7. #7
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    Thanks for the responses. I bit the bullet and purchased a derailleur hanger adjustment tool and lo and behold the new hangers were out of alignment. adjusted them and shifts perfectly now.

  8. #8
    'brifter' is a lame word.
    Reputation: cxwrench's Avatar
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    Good to hear you got it working.
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    I've got some bikes, some guns,
    and a bunch of skateboards

  9. #9
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    Let's all say it together: a new derailleur hanger is not necessarily a properly aligned derailleur hanger. Until you check/adjust it with the proper tool, then the safe assumption is that it is not aligned.

    Glad the OP worked it out!

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