2010 Chorus change for lower gears

My wife needs lower gearing (our house is at 2900 meters!). She has a Wilier with 2010 Chorus, 11 speed, compact (50 - 34) and 12 - 27 cassette. I figure the easiest alternative is to swap the cassette for a 12 - 32 which would require a new medium length Chorus derailleur. My question is whether this would necessitate a new shifter. I have heard that Campy made some changes around 2015 and the new shifter is not compatible with the older derailleur. Is this true? Also, I am assuming that a new Centaur 12 - 32 cassette would work fine with the new Chorus derailleur.

I suppose the other option is to replace the entire unit with Centaur, but then she would have a bike half Chorus and half Centaur and that would be a little funky!

Thanks for any suggestions. She won't be riding anytime soon ... it's still snowing today!
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Comments

  • pblakeney
    pblakeney Posts: 25,597
    I recently went through similar with Athena and your assumptions are correct.
    To get a 32 tooth sprocket to work you need new levers and derailleurs. Your choice is between new Chorus 12-speed, 2nd hand Chorus 11-speed, and Centaur 11-speed.
    Left field is a derailleur extender. Not recommended but supposed to work. You'll need a 14-32 cassette to work though. The derailleur can only cope with an 18 tooth difference. An 11-29 for example.
    The above may be fact, or fiction, I may be serious, I may be jesting.
    I am not sure. You have no chance.
    Veronese68 wrote:
    PB is the most sensible person on here.
  • MattFalle
    MattFalle Posts: 11,644
    or a Wolf tooth rear mech lowering thingy may work?
    .
    The camera down the willy isn't anything like as bad as it sounds.
  • pblakeney
    pblakeney Posts: 25,597
    MattFalle said:

    or a Wolf tooth rear mech lowering thingy may work?

    That's what I meant by derailleur extender. Not sure of the correct name.
    The above may be fact, or fiction, I may be serious, I may be jesting.
    I am not sure. You have no chance.
    Veronese68 wrote:
    PB is the most sensible person on here.
  • Thanks for the suggestions. The lowering device doesn't seem like a very elegant solution, although in the end it may be an inexpensive solution to try. I'd prefer PB's recommendation, so I think I'll try to find a second-hand older model medium length Chorus 11-speed and get the 12-32 cassette. I'll see just what eBay has to offer!

    If it all works out, I'll update my post, although that won't be until June!
  • pblakeney
    pblakeney Posts: 25,597
    Just FYI, I found second hand prices were too close to new prices but if that is your preferred option then new does not exist.

    For full disclosure, I went for Centaur but that is purely because I wanted silver finishing. Nothing to do with cost of the levers and derailleurs. The cost of 12-speed chains and cassettes however...
    The above may be fact, or fiction, I may be serious, I may be jesting.
    I am not sure. You have no chance.
    Veronese68 wrote:
    PB is the most sensible person on here.
  • I wasn't aware that a pre-2015 chorus or above rear mech was available with a medium cage. I thought they only did chorus as a short cage option which would accommodate a max 29 tooth cassette.

    The other option you have is to buy, or borrow for now, the 32 cassette and try and see if you have enough adjustment in the b-screw to make this work - you may find it's possible. It may not be perfect shifting but may assist for now at least.

    The other option then if that doesn't work is to go for a miche cassette with a 30 tooth max and do the same - would that give a low enough ratio do you think?

    If you do end up going for a post 2015 shifter and mech then it's worth noting that if you can't find a chorus rear mech with a medium cage then you can switch the pulley cage from the same era potenza medium mech as they are the same part number across potenza/chorus/record - RD-RE102M.

  • MattFalle
    MattFalle Posts: 11,644

    I wasn't aware that a pre-2015 chorus or above rear mech was available with a medium cage. I thought they only did chorus as a short cage option which would accommodate a max 29 tooth cassette.

    The other option you have is to buy, or borrow for now, the 32 cassette and try and see if you have enough adjustment in the b-screw to make this work - you may find it's possible. It may not be perfect shifting but may assist for now at least.

    The other option then if that doesn't work is to go for a miche cassette with a 30 tooth max and do the same - would that give a low enough ratio do you think?

    If you do end up going for a post 2015 shifter and mech then it's worth noting that if you can't find a chorus rear mech with a medium cage then you can switch the pulley cage from the same era potenza medium mech as they are the same part number across potenza/chorus/record - RD-RE102M.

    that last para is mega info - grazie!
    .
    The camera down the willy isn't anything like as bad as it sounds.
  • pblakeney
    pblakeney Posts: 25,597
    They did exist, although impossible to find now. That they existed means that spare cages should be available.

    https://thecycleclinic.co.uk/products/campagnolo-chorus-11-speed-rear-derailleur-rear-medium-cage-rd-ch002m
    The above may be fact, or fiction, I may be serious, I may be jesting.
    I am not sure. You have no chance.
    Veronese68 wrote:
    PB is the most sensible person on here.
  • MattFalle
    MattFalle Posts: 11,644
    Aaah, Malcolm's place, non?
    .
    The camera down the willy isn't anything like as bad as it sounds.
  • pblakeney said:

    They did exist, although impossible to find now. That they existed means that spare cages should be available.

    https://thecycleclinic.co.uk/products/campagnolo-chorus-11-speed-rear-derailleur-rear-medium-cage-rd-ch002m

    That's the post 2015 version though not the pre-2015. The pre-2015 spare parts catalogue, which is freely available through the Campag website, doesn't have a medium cage chorus/record/SR rear mech.

    Looking back through it again the only 11 speed with anything other than a short cage rear mech is the athena triple version. Centaur was only available with a medium cage in 10 speed.
  • pblakeney
    pblakeney Posts: 25,597
    I think the OP is already resigned to getting new 2nd hand levers.
    All new Chorus stuff is 12-speed.
    The above may be fact, or fiction, I may be serious, I may be jesting.
    I am not sure. You have no chance.
    Veronese68 wrote:
    PB is the most sensible person on here.
  • lesfirth
    lesfirth Posts: 1,382



    If you do end up going for a post 2015 shifter and mech then it's worth noting that if you can't find a chorus rear mech with a medium cage then you can switch the pulley cage from the same era potenza medium mech as they are the same part number across potenza/chorus/record - RD-RE102M.

    Simply changing the pulley cage will only give extra chain wrap ( the amount of slack chain that can be taken up). It will not increase the size of the biggest sprocket that can be used.
  • lesfirth said:



    If you do end up going for a post 2015 shifter and mech then it's worth noting that if you can't find a chorus rear mech with a medium cage then you can switch the pulley cage from the same era potenza medium mech as they are the same part number across potenza/chorus/record - RD-RE102M.

    Simply changing the pulley cage will only give extra chain wrap ( the amount of slack chain that can be taken up). It will not increase the size of the biggest sprocket that can be used.


  • MattFalle
    MattFalle Posts: 11,644
    no smaller front chainrings available?
    .
    The camera down the willy isn't anything like as bad as it sounds.
  • lesfirth
    lesfirth Posts: 1,382

    lesfirth said:



    If you do end up going for a post 2015 shifter and mech then it's worth noting that if you can't find a chorus rear mech with a medium cage then you can switch the pulley cage from the same era potenza medium mech as they are the same part number across potenza/chorus/record - RD-RE102M.

    Simply changing the pulley cage will only give extra chain wrap ( the amount of slack chain that can be taken up). It will not increase the size of the biggest sprocket that can be used.


    The difference between the "short cage " derailleur and " medium cage" derailleur is not simply the size of the pulley cage. Putting a medium pulley cage on a "short cage " derailleur does not make it into a "medium cage" model.
  • With regard to the post 2015 campag rear derailleur I believe this is exactly the case. There is no difference between the other derailleur parts and is as simple as medium cage in replacement of a short cage.



    Out of genuine interest and in relation to Campagnolo, which other parts do you believe should be or are different?
  • alwaystimetotorque
    alwaystimetotorque Posts: 226
    edited April 2022
    MattFalle said:

    no smaller front chainrings available?

    Not with a double chainset I don't believe - 34 is smallest [edit: on a campag double chainset as they OP has]
  • MattFalle
    MattFalle Posts: 11,644
    Someone like Fibrelyte say they can make any size you like in any bcd - maybe worth a quick bell?

    expensive but v cool and if they do the job then its worth it.

    MTB crankset just set up as a double?
    .
    The camera down the willy isn't anything like as bad as it sounds.
  • masjer
    masjer Posts: 2,512
    2900 metres! Be kind to your wife and buy her an E-bike for her birthday. That's if the sherpas will lug up to your house. :)
  • MattFalle said:

    Someone like Fibrelyte say they can make any size you like in any bcd - maybe worth a quick bell?

    expensive but v cool and if they do the job then its worth it.

    MTB crankset just set up as a double?

    Not sure that's really possible - I get the larger size possibility of this but not the smaller. The BCD and the amount of material between the bolt and the bottom of the teeth becomes the limiting factor. There is a finite offset between BCD and PCD of the teeth.
  • MattFalle
    MattFalle Posts: 11,644

    MattFalle said:

    Someone like Fibrelyte say they can make any size you like in any bcd - maybe worth a quick bell?

    expensive but v cool and if they do the job then its worth it.

    MTB crankset just set up as a double?

    Not sure that's really possible - I get the larger size possibility of this but not the smaller. The BCD and the amount of material between the bolt and the bottom of the teeth becomes the limiting factor. There is a finite offset between BCD and PCD of the teeth.
    as i said, best to csll yhrm as they make them and Fibrelyte are very, very good st what tbey do.
    .
    The camera down the willy isn't anything like as bad as it sounds.
  • That's up to the OP.
    I'm sure they are very good and know loads more about this than you or I, but I really don't see how they can physically make a chainring with the diameter of the teeth that is less than the BCD in a double chainring set up.
  • mercia_man
    mercia_man Posts: 1,431
    I think Matt’s on the right lines rather than faffing around with new shifters and mechs and worrying about compatibility between the various years of Campag. But I don’t think you could lose more than one tooth of the 34 little ring. My personal choice would be a super compact chainset of 46/30 or 48/32, plus I would fit a 12-29 cassette as well. That would give a really good bottom gear or two for big climbs. Campag now does super compacts, Spa Cycles do a wide range and there are plenty of other makes about. I think the Miche Graff looks a good cheap option, for example from Cycle Clinic
    https://thecycleclinic.co.uk/products/miche-graff-sub-compact-chainset-double
  • MattFalle
    MattFalle Posts: 11,644
    edited April 2022
    who knoes.

    i personlly don't know how people can make a robot with an inbuilt camera, fly it a million miles in a rocket, land it, drive the robot out and shooooom it around send pictures back to earth but they do.
    .
    The camera down the willy isn't anything like as bad as it sounds.
  • DeVlaeminck
    DeVlaeminck Posts: 8,719
    masjer said:

    2900 metres! Be kind to your wife and buy her an E-bike for her birthday. That's if the sherpas will lug up to your house. :)

    It's got to be worth considering.

    To be honest and not trying to belittle individual experience 34*29 (which I think would work with the existing set up) is a pretty low gear for road use - I'm not convinced going to 34*32 is going to make much difference unless she's riding a lot of short very steep Honister type gradients where you just want the lowest gear you can get. I'd probably be thinking of fitting a 32 too if it went straight on I'm just not sure it's worth extra expense as I don't think it'll solve the problem*.

    If it's just loads of climbing at more "normal "gradients to an extent that just requires the ability to produce power to weight over decent periods and an e-bike is going to help with that.

    * Hopefully that doesn't sound like me saying anyone that can't climb on a 34*29 should give up.
    [Castle Donington Ladies FC - going up in '22]
  • lesfirth
    lesfirth Posts: 1,382

    With regard to the post 2015 campag rear derailleur I believe this is exactly the case. There is no difference between the other derailleur parts and is as simple as medium cage in replacement of a short cage.



    Out of genuine interest and in relation to Campagnolo, which other parts do you believe should be or are different?

    The aluminium bits that form the main part of the mech. Think about it. The thing that limits the size of the big sprocket is the space between the top jockey wheel centre and the centre of the line of the hub. To get a bigger cassette in that space the top jockey wheel has to be lower. There is no way altering the pulley cage can do that.
  • As you can see from the spare parts catalogue there is no difference between the main part of the rear mech. Therefore the difference is in the cage.

    I've never measured this but will when I get home. The mounting point for the top
    jockey wheel must be lower relative to the pivot on the medium cage than on the short cage therefore making the top jockey wheel lower and therefore giving the added clearance.

    The short/medium cages are stamped either -29/-32.
  • foxhollow67c
    foxhollow67c Posts: 4
    edited April 2022
    Update from the Campy rep today. First, I had no idea I would generate such a topic of discussion, and I truly appreciate the comments and suggestions. The Campy rep called from California today and said that I could simply get a medium length cage and a qualified shop in Boulder could do the swap ... he said it was a bit tricky. Then, new 12 - 32 cassette and chain and it should work. I'll let you all know how it went, depending on when I can make the drive to Boulder (120 Km), and when they can get the derailleur part. Crossing my fingers on this one ... and I have all of your suggestions to sort through should this potentially easy swap not really work. It's never over 'till it's over!

    And I think @alwaystimetotorque has it nailed, as the Campy rep said. Thanks!
  • foxhollow67c
    foxhollow67c Posts: 4
    edited April 2022
    Oh, and as for @masjer and his/her suggestion that I cut my losses and simply get my wife an e-bike ... the mere suggestion would be a sure-fire way to a divorce. Just sayin'...!!
  • lesfirth
    lesfirth Posts: 1,382

    As you can see from the spare parts catalogue there is no difference between the main part of the rear mech. Therefore the difference is in the cage.



    I will be polite and just say that is nonsense.

    I would have less confidence in my opinion if the Campy rep said it "will" work rather than "should". I will not go as far as to say that I will show my rear end on the town hall steps if it does but I still don't think it will.