Question on mixing Ultegra cassette w/DA rear derailleur
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Question on mixing Ultegra cassette w/DA rear derailleur
Hi all ~
Upgraded to a "new bike" (going from an older 2014 Focus Cayo 3, to a 2016 Specialized Tarmac w/some DA components), and have a question about compatibility...
The rear end has Ultegra components: an Ultegra 8000 11-32T cassette, and an Ultegra 8000 11 speed rear derailleur. The front has a DA 9100.
I want to upgrade the RD to a DA 9100, so it's "full DA". My questions are:
1) Can a RD-R9100 work with this cassette? From what I'm trying to figure out, and have read so far, the 9100 RD would work with 11-30's, and might not work with this cassette. Seems this model is only made as a "short"?
2) If that's true, then I would need to replace both - the cassette AND rear derailleur?
3) The chain is in good shape - would this need to be replaced as well?
Appreciate the help!
Aurelio
Upgraded to a "new bike" (going from an older 2014 Focus Cayo 3, to a 2016 Specialized Tarmac w/some DA components), and have a question about compatibility...
The rear end has Ultegra components: an Ultegra 8000 11-32T cassette, and an Ultegra 8000 11 speed rear derailleur. The front has a DA 9100.
I want to upgrade the RD to a DA 9100, so it's "full DA". My questions are:
1) Can a RD-R9100 work with this cassette? From what I'm trying to figure out, and have read so far, the 9100 RD would work with 11-30's, and might not work with this cassette. Seems this model is only made as a "short"?
2) If that's true, then I would need to replace both - the cassette AND rear derailleur?
3) The chain is in good shape - would this need to be replaced as well?
Appreciate the help!

Aurelio
#2
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I recently upgraded components on my wife's Bianchi with the exact combo you're referring to- Ult. 11-32 cassette & DA RD-9100 I can assure you it works & her bike shifts flawlessly. You might check chain length if you're going up in cassette size also the chainstay dim. might be different enough to affect the chain length.
West
West
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Thanks, 2seven0
If I can ask a follow up - is there different RD-R9100's out there? What I see with the one I'm looking to buy is that it's a "small-direct" size. If there is another version of this that would/should work, or that there is only one version of this derailleur...
Thanks again!

If I can ask a follow up - is there different RD-R9100's out there? What I see with the one I'm looking to buy is that it's a "small-direct" size. If there is another version of this that would/should work, or that there is only one version of this derailleur...
Thanks again!
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Thanks, 2seven0
If I can ask a follow up - is there different RD-R9100's out there? What I see with the one I'm looking to buy is that it's a "small-direct" size. If there is another version of this that would/should work, or that there is only one version of this derailleur...
Thanks again!

If I can ask a follow up - is there different RD-R9100's out there? What I see with the one I'm looking to buy is that it's a "small-direct" size. If there is another version of this that would/should work, or that there is only one version of this derailleur...
Thanks again!
See the parts diagram.
https://www.paul-lange.de/tradepro/s...9100_4058B.pdf
A derailleur marked "Direct Mount" may be shipped without the part marked 1 in the diagram (Y5ZR98020 Bracket Axle Unit (for normal type))
Presumably some of the new bikes are designed for Shimano's direct mount, but 99% of the older bikes will require that adapter.
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Shimano has a page for parts compatibility.
2018-2019 SHIMANO Product Information Web
It says that an RD-R9100 isn't officially supported with an 11-32 cassette. This doesn't mean that it won't work, only that you are on your own if you try.
As others have said, it likely will work but your mileage may vary.
But always start at the Shimano site to find out what they actually support.
-Tim-
2018-2019 SHIMANO Product Information Web
It says that an RD-R9100 isn't officially supported with an 11-32 cassette. This doesn't mean that it won't work, only that you are on your own if you try.
As others have said, it likely will work but your mileage may vary.
But always start at the Shimano site to find out what they actually support.
-Tim-
Last edited by TimothyH; 03-27-19 at 02:24 PM.