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Micro compact chainset compatibility

graemevetgraemevet Posts: 61
edited January 2018 in Workshop
I'm confused by various standards and I hope that someone can help. I'm only little and in order to help on super steep hills I want to change the chainset on my 2015 Canyon Endurace. I'm currently running a 105 5800 34/50 chainset. Press fit bottom bracket (?BB30?).

I want to run one of these in 30/46 spec:
https://www.suginoltd.co.jp/us/products/road/ox.html

Am I correct in thinking that the Shimano 5800 chainset shares the same 24mm spindle diameter as the Sugino one or would I require some sort of adapter for the bottom bracket?

Does anyone know if this would cause any issue to the 5800 Front Mech? FYI I have a GS 5800 rear mech and an 11-32 cassette.

Thanks

Graeme

Posts

  • Alex99Alex99 Posts: 1,407
    graemevet wrote:
    I'm confused by various standards and I hope that someone can help. I'm only little and in order to help on super steep hills I want to change the chainset on my 2015 Canyon Endurace. I'm currently running a 105 5800 34/50 chainset. Press fit bottom bracket (?BB30?).

    I want to run one of these in 30/46 spec:
    https://www.suginoltd.co.jp/us/products/road/ox.html

    Am I correct in thinking that the Shimano 5800 chainset shares the same 24mm spindle diameter as the Sugino one or would I require some sort of adapter for the bottom bracket?

    Does anyone know if this would cause any issue to the 5800 Front Mech? FYI I have a GS 5800 rear mech and an 11-32 cassette.

    Thanks

    Graeme

    I think so. Clicking on their BB link takes you to their BB30 to ID24 bottom bracket. Says to me that this has a 24 mm axle. Lovely looking chainset BTW.
  • arlowoodarlowood Posts: 2,527
    graemevet wrote:
    I'm confused by various standards and I hope that someone can help. I'm only little and in order to help on super steep hills I want to change the chainset on my 2015 Canyon Endurace. I'm currently running a 105 5800 34/50 chainset. Press fit bottom bracket (?BB30?).

    I want to run one of these in 30/46 spec:
    https://www.suginoltd.co.jp/us/products/road/ox.html

    Am I correct in thinking that the Shimano 5800 chainset shares the same 24mm spindle diameter as the Sugino one or would I require some sort of adapter for the bottom bracket?

    Does anyone know if this would cause any issue to the 5800 Front Mech? FYI I have a GS 5800 rear mech and an 11-32 cassette.

    Thanks

    Graeme

    Since the link you provided states that it is 24mm axle compatible then you should have no problem using that crankset with you existing Shimano BB.

    FD might be more of an issue if you have a braze on type fitting as there may not be enough adjustment to allow the FD to drop low enough for the smaller cranks. If the fitting is band on then you should be fine.
  • keef66keef66 Posts: 13,123
    That looks like it would just be a straight swap, so you could leave whatever BB you have in there (it won't be bb30. Shimano press-fit in a BB86 bottom bracket shell I'm guessing)

    You'll likely need to shorten your chain and drop the front mech down a bit.

    The front mech is the only thing you need to check. Will it be feasible to lower it a bit? If a braze-on mount, is there room in the slot to slide it down? If a band-on, does the shape of the seat tube allow you to loosen it and slide it down?

    On my winter bike I've fitted a 46/36 CX chainset and the band-on mount would only drop a bit before it fouled the lower bottle cage boss, so the mech sits a little higher than I'd like. It still shifts sweetly though and I've never dropped the chain
  • Thanks everyone - I think you've all uncovered the incompatibility that I didn't spot - Looking at the braze-on mount I don't think it'd drop much lower that it already does so I'd run the risk of dropped chains and poor shifting.

    Looks like plan B (keep current chainset):
    Shimano XTR M-9000 SGS rear mech
    11-40 or 11-36 casette
    JTEK Shiftmate 8a

    As a bonus it means I can continue to use my Stages power meter.

    I think its time I went to see my local bike mechanic!
  • Alex99Alex99 Posts: 1,407
    graemevet wrote:
    Thanks everyone - I think you've all uncovered the incompatibility that I didn't spot - Looking at the braze-on mount I don't think it'd drop much lower that it already does so I'd run the risk of dropped chains and poor shifting.

    Looks like plan B (keep current chainset):
    Shimano XTR M-9000 SGS rear mech
    11-40 or 11-36 casette
    JTEK Shiftmate 8a

    As a bonus it means I can continue to use my Stages power meter.

    I think its time I went to see my local bike mechanic!

    The new R8000 rear mechs can take a 34 sprocket officially, and I wouldn't be surprised if a 36 would be fine. That would work with your 5800 shifters with no shiftmate.
  • mercia_manmercia_man Posts: 1,406
    This adapter lowers braze on front mech to suit smaller rings. It comes from the USA but they do ship internationally.

    https://wickwerks.com/products/fit-link-adapter/
  • mercia_manmercia_man Posts: 1,406
    Just noticed similar thing from Sugino:

    https://www.suginoltd.co.jp/us/products ... #pnH4MT-OX
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