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Road shifter and FD for a MTB crank

wtherapywtherapy Posts: 36
edited January 2019 in Workshop
Hello,

I would like to build a 3x11 climbing road bike using this mtb 3x11 crankset:

https://bike.shimano.com/en-EU/product/ ... 000-3.html

I want road / drop handlebar -> so road shifter.
Change the shifter, change the FD, whatever.
Is there any combination in this world to do this?

Posts

  • imposter2.0imposter2.0 Posts: 11,727
    Not really sure what it is you are asking - to run a triple, all you need is a triple-compatible l/h shifter..
  • Imposter wrote:
    Not really sure what it is you are asking - to run a triple, all you need is a triple-compatible l/h shifter..

    Hi,

    I just want to have a road bike setup using this crank, so I need road shifters because I want drop bars (I don't want to switch to a flat bar).
    I will choose an 11-25 11 speed cassette afterwards or so, road cassette, road rear derailleur, they should work.
    The question is whether there is a road left (chainrings) shifter and a front deraileur that would work with this crank.
  • just buy an e-bike
  • just buy an e-bike

    sorry I don't plan on climbing Zoncolan with TT chainrings. But thanks for your time.
    Any technical person that can answer this (and only this) question?
  • I suspect you can't... LH shifters are not designed with enough cable pull to swing the FD all the way through 3 rings.

    That said, it might well be that a FD with a higher pull-to-swing ratio exists on the market... it would lose accuracy and chain might occasionally drop.

    A (poor) solution would be to have a LH shifter from the Claris range, which is designed for triple and a RH shifter from an 11 speed groupset...

    or you can go full Claris and 3 x 8 speed
  • Actually Tiagra exists as triple and it's 10 speed... so gor Tiagra, it's a very good groupset... who needs 11 sprockets?
  • imposter2.0imposter2.0 Posts: 11,727
    wtherapy wrote:
    The question is whether there is a road left (chainrings) shifter and a front deraileur that would work with this crank.

    Lots of road/touring bikes use a triple setup - so yes.
  • imposter2.0imposter2.0 Posts: 11,727
    Actually Tiagra exists as triple and it's 10 speed... so gor Tiagra, it's a very good groupset... who needs 11 sprockets?

    As does 105 and Ultegra. If not current models, then certainly recent.
  • Hi all,

    thanks for the answer, but 3x10 is basically equivalent to 2x11, that's why I'd like to go for 3x11.
    From your posts I'd take that a mtb FD would not shift ok because of different pull ratio and a road FD would have problems because of the chainline and chainrings spacing of the mtb crank?
  • arlowoodarlowood Posts: 2,538
    Actually Tiagra exists as triple and it's 10 speed... so gor Tiagra, it's a very good groupset... who needs 11 sprockets?

    Yep - Ugo's suggestion is a good one unless of course you decide to go hybrid and use a Tiagra LH shifter to operate the triple chainset and a compatible 11-speed RH shifter to give you 11 sprocket options on the rear cassette (105, Ultegra etc)

    One factor that might scupper your plan is the frameset you are adding this to. Most road frames with braze-on FD mounts have the mounts positioned to accommodate 53 or 50t chainrings. If you fit a chainset with a 40t maximum chainring there may be problems getting the FD low enough to ensure accurate shifting. You might be able to bodge it by filing out the braze on mount but that may not be ideal.

    Frames with a band-on FD should be fine as long as the FD can be moved low enough without other bits getting in the way.
  • arlowood wrote:
    Actually Tiagra exists as triple and it's 10 speed... so gor Tiagra, it's a very good groupset... who needs 11 sprockets?

    Yep - Ugo's suggestion is a good one unless of course you decide to go hybrid and use a Tiagra LH shifter to operate the triple chainset and a compatible 11-speed RH shifter to give you 11 sprocket options on the rear cassette (105, Ultegra etc)

    One factor that might scupper your plan is the frameset you are adding this to. Most road frames with braze-on FD mounts have the mounts positioned to accommodate 53 or 50t chainrings. If you fit a chainset with a 40t maximum chainring there may be problems getting the FD low enough to ensure accurate shifting. You might be able to bodge it by filing out the braze on mount but that may not be ideal.

    Frames with a band-on FD should be fine as long as the FD can be moved low enough without other bits getting in the way.

    Hi,

    thanks for the answer. I am fine with using a mixed combination of LH shifter of any kind and a 11 sp RH shifter. My frame is an old CX Cinelli Zydeco 2011 (rim brake) and I don't think there would be problems with the small rings.
    I already have a Tiagra 3 sp LH shifter but don't mind buying a different model if this one doesn't work (maybe Campagnolo would work for the FD?).
  • mercia_manmercia_man Posts: 1,426
    Another option is bar end shifters. For example, my wife runs a 105 triple chainset with 105 triple mech and Dura Ace nine speed bar end shifters. The front shifter is non-index ratchet so will work pretty well anything.

    Campag ergo shifters (not the later lower end index ones) also work on a non-index infinite ratchet so they will shift a triple very well. It’s just a question of adjusting the mech stops. I am not sure about cable pull on more recent 11-speed Campag but all the old nine speed ones from Record to Veloce were effectively the same mechanism and much less finicky for setting up than Shimano indexed triple STI levers. I have used Veloce shifters from around 2003 on my triple. Later Veloce were downgraded to a different non-ratchet system.

    As for front mechs, I used a Chorus double for years on the triple chainset on my tourer. It worked fine. I later replaced with a Centaur triple mech which is admittedly s bit better. I tried a 105 triple FD with my Veloce levers but it didn’t work too well as the Veloce levers obviously pull less cable than ideal for that mech.
  • Anyone has any idea whether this [ http://www.jtekengineering.com/shiftmate/shiftmate-7/ ] might work?
  • keef66keef66 Posts: 13,123
    wtherapy wrote:
    thanks for the answer. I am fine with using a mixed combination of LH shifter of any kind and a 11 sp RH shifter. My frame is an old CX Cinelli Zydeco 2011 (rim brake) and I don't think there would be problems with the small rings.
    I already have a Tiagra 3 sp LH shifter but don't mind buying a different model if this one doesn't work (maybe Campagnolo would work for the FD?).

    Since you have a CX frame and a triple LH shifter I'd just try a Tiagra triple FD to see if it works. Cheap enough on Ebay.

    Not sure about your BB shell width or what BB you'll use, but you might have to use spacers to get the chainline spot on.

    I have a 9 speed Tiagra double FD & shifters working well with a 46/36 CX chainset despite the fact the frame won't let me drop the FD down as far as I'd like.
  • keef66keef66 Posts: 13,123
    wtherapy wrote:
    Anyone has any idea whether this [ http://www.jtekengineering.com/shiftmate/shiftmate-7/ ] might work?

    They seem to think it will. So you could have a MTB triple FD to match your cranks, and your Tiagra triple shifter

    ETA Christ! They are 30 quid each!
  • Why 3 x 10 is the same as 2 x 11? That's nonsense

    An 11 cassette has an extra sprocket wedged in the middle, typically between a 14 and a 16, but it doesn't have more range. Tiagra 10 speed cassettes with 34 and 36 T sprockets do exist
  • mercia_manmercia_man Posts: 1,426
    Although I've benefited hugely from a triple in my years of touring with camping gear in the Alps and Pyrenees, I think the new breed of super compact double chainsets combined with a wide range 11-speed cassette would be the way I would go now. Something like a 46/30 chainset and 11-34 cassette would give me the same bottom gear as I have now, enabling me to ride loaded up any hill. The only disadvantage compared with a triple is the annoying 16-tooth jump between rings. I guess I would also miss the small jumps between cogs on my 13-28 nine-speed cassette.
  • keef66keef66 Posts: 13,123
    I have a conventional 50/39/30 105 triple on my best bike. I like the manageable jumps between chainrings (as I do with the 46/36 CX chainset) and think a compact with a 16t jump would only annoy me. For me the only downside is the exposed gear cables making the bars look untidy and getting in the way of the front light / bar bag. First world problems I know.

    I was idly speculating that a super compact chainset would allow me to upgrade to R7000 so neatening the bars while retaining my very low climbing gears. At my age I'm not so fussed about losing the 50t chainring.
    But then my 10 speed wheels would only work with the 11 speed HG cassette with its massive range and big jumps, so maybe that would annoy me too...

    Maybe the Tiagra 4700 triple shifters / mechs would be a better solution?

    Or maybe put the money towards a new bike as a retirement treat, then I can have a few things I can't have on this frameset like wider tyres and hydraulic disc brakes.

    Can Di2 manage a triple??
  • keef66keef66 Posts: 13,123
    Hmm, I've read elsewhere that the MTB chainset is likely to have a wider chainline than a road one. So it will put the rings a lot further outboard. Maybe too far for the road FD to work?
  • keef66 wrote:
    Hmm, I've read elsewhere that the MTB chainset is likely to have a wider chainline than a road one. So it will put the rings a lot further outboard. Maybe too far for the road FD to work?

    That is my worry too, but I have used road STI with a MTB FD in the past... mind you, it was not a triple...
  • keef66 wrote:
    Hmm, I've read elsewhere that the MTB chainset is likely to have a wider chainline than a road one. So it will put the rings a lot further outboard. Maybe too far for the road FD to work?

    I guess the idea is to make the MTB FD work with the road shifters. Hard to believe the road FD will work with the MTB crank.
  • mercia_manmercia_man Posts: 1,426
    Have a look at this debate. Looks like Deore MTB triple works fine with Tiagra FD plus other relevant stuff for you.

    https://forum.cyclinguk.org/viewtopic.php?f=5&t=72121
  • trek_dantrek_dan Posts: 1,366
    keef66 wrote:
    Hmm, I've read elsewhere that the MTB chainset is likely to have a wider chainline than a road one. So it will put the rings a lot further outboard. Maybe too far for the road FD to work?
    Anecdotal perhaps (as its setup 1x) but I use XTR MTB cranks on one of my CX bikes because I like the wider Q factor, I would be surprised if could run a conventional road FD and double rings, it does push things out a fair bit further.
  • I believe that as long as the cranks and the FD are compatible, the shifter won't matter.

    If you use a road shifter and MTB FD and chainset you should be fine. As long as they are all triples.

    For fronts, you can even mix SRAM AND Shimano.
  • Hi,

    thanks everyone for your support. I've ordered the Shiftmate7 and the SHIMANO XT Crank 3-speed FC-M8000-3, together with FD-M8000-H FD. Let's see how it goes :). Hope my old Tiagra LH (from an old 3x9) will be good enough.
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