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Electronic groupset installation help and suggestions/recommendations

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Electronic groupset installation help and suggestions/recommendations

Old 06-03-20, 10:10 AM
  #1  
cpunerd
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Electronic groupset installation help and suggestions/recommendations

TLDR: I want to upgrade our 52-39-30,11-36 mechanical shifting +hydraulic brakes road tandem to an electronic groupset (no preference as to which manufacturer) and we have no clear idea how to go about doing it. I'd love to get some help and have included questions and bike specs in the bottom.

(Lots of bike specs at the very bottom)

Hi fellow tandem riders, my wife and I have been riding a Dolan road tandem from the UK for two years now and we've been quite happy with it. Save for one thing, the shifting. We tweak, retighten, and replace our shifter cables more frequently than I'd care to admit, but it seems like all it takes is a ride or two for shifting to become problematic. The front has problems shifting into the big ring quite frequently. And the rear needs a double shift up in order to switch, but usually only a single downward shift to move. Our exact setup is detailed below, and what we're looking at is switching from the mechanical shifters + hydraulic disc brakes to an electronic groupset, again with hydraulic disc brakes. We have a pretty wide range with our triple (52-39-30) and rear cassette (11-36) with a Wolf Tooth Road Link adapter. We're willing to sacrifice *some* of our top-end speed as long as we don't lose much (or hopefully) any of our lower gears. We live in Switzerland and there's lots of 12%+ climbs that we do around here that would simply wipe us out if we didn't have our low-end gears. All of the electronic groupsets that I've seen are either 1x or 2x, hence why I mention the concern about gear ratio (going from a 3x to a 2x).

I'm perfectly comfortable servicing/installing mechanical parts on our tandem. But I have zero experience installing/servicing electronic components and have a bunch of questions. I guess I could start with the following:
  • Recommendations for SRAM vs Shimano vs other?
  • For Di2, I know we need extra pieces - the two junction boxes and the battery pack. We don't have any internal routing on our frame so I'm not sure where the rear junction box or battery pack would best be placed. Any suggestions? Pictures of custom solutions would be amazing.
  • Do we need to worry about the chain line? We have an Alpina front-derailleur adapter into which is mounted a braze-on Tiagra 3x front derailleur. The rear derailleur is a vanilla Tiagra, though we have a road link on it.
  • What do we do about the crank set? I'm guessing we can't go with a standard crank set because it has no captain-crank connection on the non-drive side. So I have no idea what to do about it.
    • Buy the groupset and get some supplementary chain rings?
    • Do I need to worry about chain-ring spacing?
      • Only about it being too large but not too small?
      • Can I just adjust the high and low limit screws on the front derailleur if the spacing is small?
  • We have TRP hydraulic brakes and we're quite happy with them. I don't see any particular need to change to a different brake system, but if we do, are there solutions for hose lengths?
    • I remember looking around and seeing that SRAM doesn't warranty their brake levers for tandems.
  • If we go with eTap over Di2, is it recommended to get new wheels, or to replace the hubs on our current wheels. I ask because I believe eTap is 12x and can go down to 10 teeth in the rear, and therefore doubly won't fit on 10/11-speed hubs. I could, of course, be wrong.
I'm sure I'm forgetting a bunch of things, so I'll probably ask them in a follow up as other posts remind me.

Bike specs:
  • Shimano Tiagra 3x10 drop-bar shifters
  • 52-39-30 chain set
    • Big-middle connection is 130 mm BCD
    • Middle-little connection is 74 mm BCD
    • 5-bolt symmetric star pattern with spiders
  • Non-drive side is 42T, 130 mm BCD with a 5-bolt symmetric star pattern
  • TRP HYRD hydraulic disc brakes both front and rear
  • W/24-22mm spindle & BSA Bottom Bracket
  • Mavic A719 wheel set with Shimano Deore hubs.
  • Not sure it matters much but we have 175 mm cranks in the front and 150 mm cranks in the back.

Thanks so much for any help/recommendations you can give.
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Old 06-03-20, 09:03 PM
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WheelsNT
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If you want to go electronic for some of the benefits of electronic, such as shift programming, crisper front downshifts, etc.,that’s great. However, something’s wrong with your current mechanical setup, it should work way better than that. Granted, my experience is mostly more-so with Ultegra / 105 / XT / XTR, and I think Tiagra is a notch lower grade, but still, it ought to shift better than that unless it’s completely worn out. How many miles on the Tiagra stuff? Shifters gummed up with old grease and not actually shifting when you move them? Lots of play in the derailleur pivots? Possibly cheap shift cable casing with a lot of compression flex in it? Something’s wrong. Others will no doubt be along soon with other ideas about things you could check. Again, if you just want to go electronic, that’s great, but don’t make that move because you don’t think mechanical can work properly. We have mechanical shifting on our quad which is twice the length of your tandem, and I never have to mess with it. My $0.02.
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Old 06-03-20, 10:04 PM
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We don't have that much distance, probably less than 4,000 km in total. And we upgraded the cables and housings after about 2,000 km with no noticeable change in performance. I think it's likely a combination of cable length and Tiagra, the latter being hard to avoid since we have a 3x in the front.

I guess the questions I have about the drive train and chain rings would apply equally well to converting from 3x to 2x if we decided to just upgrade to Ultegra shifters and derailleurs. I'm fine with replacing the cassette and rear mech but I'm not sure what a safe conversion from a 3x to 2x in the front would look like.
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Old 06-04-20, 05:19 AM
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hello from austria
i changed the drivetrain to electronic shifting on our tandem last year- same reasons as described by you;
i use sram red etap 2x11 with hydraulic brakes, which works very well.
we use cranks from gebhardt.cz with the original sram chainrings (50/34) and shimano xt or xtr casettes (11-40,11-42).
(should be compatible with your hubs)
rear derailleur is the etap wifli combined with a wolftooth road link.
length of the brake hose on the rear brake might be a problem, but was sufficent on our bike.
parts might be difficult to find (i think r2-bike has them available)

btw when we started tandeming i used 175mm cranks and changed to shorter ones, because my stoker/wife always complained about to low cadence; that change increased cadence by about 5-10 rpm and made the stoker happy.
as you use garmin vectors you could also have a look to "cycling dynamics" (power phase....) to analyse your stokers problems with power output
regards andreas
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Old 06-04-20, 07:30 AM
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I just upgraded our Co-Mo Carrera from Ultgra triple to Sram Red ETAP and couldn't be happier. We too had nothing but constant futzing with the shifting and brakes. Original gearing was 28-39-52 and 11-32 (10 sp) on the rear. New is 34-50 and 11-42 (11-sp). We got a little lower on the low end and not quite as high on the high end.

Shifting is crisp, braking is phenomenal gong from cable disc to hydraulic.

We kept the same stoker crank utilizing the inner 2 spiders (74 and 130 BCD). Finding a 34T 74 BCD ring might be a bit of a challenge. 33T are readily available, however, I don't know if it would strain the front derailieur difference.

Also, if you are going to go to hydraulic brakes, SRAM Etap has gone the flat mount so finding an previous generation brifter/brake set in post mount might take a little looking but I do see them out there. If you keep your TRP cabled brakes, you shouldn't have any issue (however, I am very happy to have ditched the Spyres and gone hydraulic)

Etap does not have all the programability as Di2, however, we have survived generations without that feature and I don't think we will miss it.

Some things to consider:
-Drivetrain capacity - The set up we have leaves the small front and gears 7 thru 11 unusable as there is not enough capacity in the derailer. Chinook Cycles sells an aftermarket cage specifically for Red Etap that increases capacity from 36 to 49 (or maybe its 47). We have one on back-order and hope to receive it soon.
-Jagwire sells a 3 meter hydraulic hose and as separate kit of fittings for specific brakes. One hose will do the rear brake.
-I am glad I did not go Di2. While owners of Di2 love it (as to owners of Etap), if your bike is not set up for internal routing, you will either be drilling holes in your frame or you will have wires and cable ties all over the place.
-Routing of the hydralic cable with very simple. I utilized the mounting holes for the cable guides under the bottom brackets and utilized 4 Problem Solvers hose clips and 4 cable ties.

I am happy to answer any other questions.

(Also, I have Tiagra, Ultegra, and Dura-ace 10 speed drive trains on verious half bikes and I must say the the Tiagra has been the best shifting of them all)
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Old 06-04-20, 08:27 AM
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Originally Posted by cpunerd View Post
We don't have that much distance, probably less than 4,000 km in total. And we upgraded the cables and housings after about 2,000 km with no noticeable change in performance. I think it's likely a combination of cable length and Tiagra, the latter being hard to avoid since we have a 3x in the front.

I guess the questions I have about the drive train and chain rings would apply equally well to converting from 3x to 2x if we decided to just upgrade to Ultegra shifters and derailleurs. I'm fine with replacing the cassette and rear mech but I'm not sure what a safe conversion from a 3x to 2x in the front would look like.
Making sure I'm reading this correctly, are you a newer team to tandeming with about 4,000km on a tandem? One of the weak links of tandems are the shifting especially on the front. If you are late on your shift and are applying too much pressure you will have bad shifts. Over the years we've gotten better and better at anticipating our shifts, and my wife (stoker) can feel when she needs to lighten-up for the front derailleur to drop the chain to a smaller ring. The electronic shifting does seem to eliminate a lot of this. I'd think the eTap is the solution best for a bike without internal wire routing. Cycles Chinook has built-up several tandems with this shifting set-up, you might want to check in with Dave Lafferty there to get some of his insights.
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Old 06-04-20, 09:44 AM
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Originally Posted by Paul J View Post
Making sure I'm reading this correctly, are you a newer team to tandeming with about 4,000km on a tandem? One of the weak links of tandems are the shifting especially on the front. If you are late on your shift and are applying too much pressure you will have bad shifts. Over the years we've gotten better and better at anticipating our shifts, and my wife (stoker) can feel when she needs to lighten-up for the front derailleur to drop the chain to a smaller ring. The electronic shifting does seem to eliminate a lot of this. I'd think the eTap is the solution best for a bike without internal wire routing. Cycles Chinook has built-up several tandems with this shifting set-up, you might want to check in with Dave Lafferty there to get some of his insights.
I understand what you're saying, but I think we're also quite good at verbally communicating. For whatever reason, non-verbal communication doesn't work well for us on the tandem so we always verbally communicate important things. *especially and always* big-ring shifts. I always give an "ease-up, shifting big ring" shout and wait for her to relax, before shifting the big ring. We don't have *any* problems shifting between the middle and small rings, or shifting from the big ring to the middle ring. We only have a problem shifting up into the big ring, which makes me believe it's more a problem with either cable tension, parts, or both. As I mentioned earlier, we've adjusted and replaced the shifting cables and housing in order to try and fix the problem, but it seems like after a few rides, the shifting deteriorates.

That also doesn't account for problems in the rear mech. It seems like we always have to shift up two clicks in order for a shift to happen. And similar to the front, we've adjusted and replaced cables frequently in order to try to address the problem. Every time we think we've fixed things, it only takes 50-100 km (basically one, maybe two, rides for us) for the shifting to deteriorate back to where it was. I'll try to get in touch with Cycles Chinook and see if they have any recommendations, thanks for the suggestion.
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Old 06-04-20, 10:10 AM
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Cherz and Alcanbrad, thanks for your sharing your experiences. The thing I'd most like to know is how you deal with going from a 3x in the front to a 2x in the front. I can't imagine that a stock eTap bottom bracket, stock chain rings, and stock cranks work. Can you share your experience around what your previous set up was in that regard? Which BB, chain rings, and cranks did you have? And what do you have? Size, BCD, bolt pattern, etc., would all be super helpful. I'm concerned that our setup might be unfortunately custom and therefore hard to change. But the other feeling I have is that it very well might be as simple as ordering two chain rings (34 and 50) and finding a way to connect them with the BB and cranks that we have, and then finding *something* to do with the space where the third chain ring currently is. I can imagine a few different scenarios playing out here, but I'm honestly not sure which one is right.

And thanks very much for the information on the long-cage adapter for eTap from Chinook. It seems like a great find, and we'll almost certainly order one if we decide to go with eTap over Di2 (which looks likely, I must say).
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Old 06-04-20, 11:14 AM
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For us, we kept the original stoker crank, FSA Gossamer MegaEXO tandem triple/bottom bracket. Bike is circa 2014 and this crankset appears to still be available. Original gearing was 28-39-52 and new is 34-50. Bolt pattern is 74 for the granny and 130 for the center and outer. You shouldn't need to worry about chainring spacing when going from 10 to 11 speed. I don't know if this holds true for going from 9-11 or others, a google search would be in order for your case. Adjustment of the FD was a breeze, and especially so that when you have to move its position on the seat tube, you don't have a taught cable to deal with. For chainrings we have a 50T pinned and ramped ring from Origin8 and the 34 is a custom made ring from House of Tandems. For our bike HOT recommended utilizing the inner and center ring positions. As for the position of the third chainring, all we had to do was remove it and use shorter chainring bolts.

The bigger question you are asking, going from 3x to 2x up front, is the one I struggled with for a few years until deciding to make the plunge. This is a question that leaves many tandem riders concerned, especially when thinking about dropping the kind of money as being contemplated here. In summary, I like the new set up much better in practice than I believed it was going to be. In fact, with the large rear cassette, many smaller hills that we would downshift to the middle ring we no longer have to and just stay in the larger ring. About a year or so ago, this transition was discussed on this forum and I did a spreadsheet analysis as to how large a change between adjacent gears actually was. By adjacent gears, I assumed that in all shifting, either in front or in rear, would occur one derailleur at a time. For example, say you were going from 50 to 34 up front, and 28 to 24 in the rear. In almost all cases, one would shift one of the derailleurs first, then shift the other, one would rarely shift both at exactly the same time. With this assumption, I learned that no shifts were greater than 6 teeth in difference in both drivetrains. What we have experienced is that the triple gives you more granularity (and overlap) than the double, however, the action of a shift is no more impactful in either set up. On top of that, the electric shift is so effortless and crisp, it becomes just a push of a button over a contemplation of a shift, waiting for the cranks to be in the optimal position, executing the shift. You just push the button and it goes there. I think the key to all of this is to utilize a wide range cassette with a road-link derailleur hanger. You can easily create a spreadsheet comparing gearing in both current and planned set ups and I think you will find as we did that we gave a little on the high end, picked up a little on the low end which we wanted, and overall it was a better experience. Do pay attention to system capacity.

I don't know if I articulated this clearly, perhaps others can add their words and a good picture can be drawn, however, bottom line, it was not as impactful as I anticipated, and is actually better than I thought it would be.
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Old 06-04-20, 12:25 PM
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We fitted the SRAM etap Wifli, rim brakes, to our Comotion Macchiato about a year ago and have never looked back. On the front, we went from 53-39-30 to 46-30 (we have combined ages of 160!) by simply removing the outer ring and installing the 46T in the centre position. For Florida riding we use a 11-36 cassette and Wolf Tooth, but the smallest three sprockets are not usable when on the small chainring - better that way to accommodate big/big, than having the chain too short, when nasty things could happen to the RD. I am thinking of fitting a longer RD cage, but we have managed so far with no problems. The shifting is smooth and effortless.
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Old 06-05-20, 01:21 AM
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hi


easiest and cheapest solution is the one alcanbrand uses- keep your cranks an look for fitting chainrings


finding tandem cranks isn't easy;


two european manufacturers i'm aware of, are gebhardt in the czech republic and middleburn in england (not sure if middleburn offers cranks shorter then 170 mm)


our duratec tandem was initially equipped with 3x cranks from gebhardt


i changed that later on to 2x (again from gebhardt) to reduce q-factor and use sram 5-hole rings with 110mm bcd


bb is a bsa isis with 113mm axle length (little bit outdated standard)


gebhadt sells cranks wit integrated axles for shimano ht2 bb too




you wont be able to use sram casettes too, but shiftingg is fine with shimano 11x mtb sprockets


(11x road casettes wont be compatible with your hub )




andreas
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Old 06-05-20, 01:36 AM
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we're talking about sram red etap 11x and not the new red axs 12x !
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Old 06-06-20, 04:15 AM
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Thanks all, with your help and feedback, I've done some research and this is the understanding that I've come to:
  • The hub that we have (FH-M6000) will support an 11-speed Shimano XT 11-40T cassette.
    • This means we don't need to get a new free hub or wheel.
  • We can swap our shifters for SRAM eTap 2x11 with mechanical brake levers.
    • I was mistaken previously when I said that our brake calipers are hydraulic. They're mechanical. Funny, I've never had a problem with braking, even on 15%+ descents, so I always assumed they were hydraulic...
  • We can swap our front and rear mechs for SRAM eTap 2x11 mechs
    • We need to get the WiFli rear mech
    • We should also get the Chinook replacement/upgrade cage to increase the capacity of the system so it can handle such a wide cassette.
    • We already have a Wolf Tooth road link, which we also need to use.
  • In order to get compatible chain rings, we need to find a set of tandem chain rings (and probably cranks)
    • Gebhardt.co.cz seems to be the best place to find such a thing
  • We may end up needing a new bottom bracket, but hopefully not.
    • The BCD of our cranks and rings is the biggest problem. We intend to go with 50/34 up front, and it's potentially not possible to connect such chain rings to our existing cranks since our cranks are 130 mm BCD.
Does that all sound right?

I think it's going to take us some time to source all of the parts, but not needing to get custom wheels will make things much easier. I'll try to report back once we finish the conversion. Thanks again for all your help!
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Old 06-06-20, 11:15 AM
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When you say get compatible chain rings/tandem chainrings, I believe you are referring to the timing rings. There is nothing tandem specific regarding 34/50 chainrings.

if your stoker crank only supports 130 bcd, you will need a different crank. Suggest you start with bike shops that are tandem focused.

im sure you know this, but since your list is well specified, You will also need an 11 speed chain (you may have to buy 2 chains to have enough links). If you want a little lower gears you can go with an 11-42 as we did. We got SRAM, but many sources are available.

good luck,
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Old 06-06-20, 12:42 PM
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inner ring bcd cannot be 130- probably 74mm
you should look for a 34 tooth ring that replaces your inner ring and mount the 50 t ring in the middle position
otherwise the chainline might exceed the capacity of the front derailleur
chainline of our bike is 46 mm (red cranks have 45 mm,i think
cheers
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Old 06-08-20, 12:27 PM
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A little late to the thread but maybe helpful...

Hi Cpunerd. I rarely contribute to the forum but wanted to pass along my recommendations. FYI, I'm most grateful to other members who have posted and have helped dearly along the way. First of all a little background on us... we've been tandeming for almost 30 years, mostly in hilly terrain and often into the Blue Ridge Mountains. We're small/light and don't need to put out a ton of watts, but do run into 15-20% grades that are typically only a few minutes but sometimes can last an hour in extreme cases. We're approaching 200km and are now into our 50's (ie. certainly less strength than past years) but our current setup allows us to still climb and enjoy these favorite routes of ours.

Three years ago we purchased our 3rd tandem and like you, I was looking to optimize my gearing in a cleaner, more reliable manner that gave us plenty of climbing gears. We also were willing to give a bit on the low gearing and ultimately came up with a combination that is perfect for us, and possibly you as well.

Our 2nd tandem had a Shimano triple front (52-42-30) and 9 speed rear (11-34) which we rode for 11 years. With our current tandem we decided to go Shimano DI2 double front (44-28) and 11 speed rear (11-40). Benefits include:
- The double to triple front has now given us very reliable, smooth shifting! We can use every front/rear gear combination, so no wasted gears and no more chain crossover!
- By going to a smaller large ring on the front (52 to 44), we've surprisingly only lost 1 gear from our previous setup (the 52 front - 11 rear combination). We can still pedal up to 51.5 kmph @ 100 rpm the few times that's useful and that's plenty for us.
- The 28 front and 40 rear gears give us all sorts of climbing ability... even if a turtle might be moving faster than us uphill. Seriously, in the highest (easiest) gear, we're doing about about 6.5 kmph but... our cadence fairly snappy and everyone's happy.
- With DI2, we no longer have shifting issues because there are no more sticky, dirty, stretched, damaged derailleur cables!
- Also with DI2, Shimano DFly (newer wireless EW now), and Garmin Edge... I can see on my Garmin Edge which front and rear gears I'm in. I can also see the battery level of the DI2 battery.

Another recommendation if possible... a Gates belt for your sync chain... much lighter, cleaner, and quieter! I initially worried about the switch but after 3 years now, am totally sold on it.

Couple more notes:
- For the 11-40 rear cassette, we needed to use the Wolf Tooth Roadlink extension which has worked perfectly. We also have an 11-44 rear cassette on the shelf for our 60's.
- The chainrings are 42t (104BCD) and 28t (64BCD). These aren't the most common but they are available by Shimano.

If you have any questions or need anything else, just let me know!
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Old 06-11-20, 11:12 AM
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Thanks jnjtandem, your story is definitely something to consider. Even more so given that our tandem may not have the frame clearance for a 34T inner ring, so going sub compact could help a lot.
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Old 07-07-20, 11:27 PM
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A quick report back. We pulled the trigger on an eTap groupset and are now in the middle of our conversion. We put the levers and derailleurs on, and we swapped our 11-36 for an 11-40 (we have a Wolf Tooth Road Link). We have yet to swap our chainrings. What this means is that we have a 52-39 in the front, and we also happen to have a 30T chainring that is only there because we haven't gotten rid of it. The current rings are 130 mm BCD and 74 mm BCD.

The shifting is SOOO much easier and nicer. Shifting in the front is a joy (love that little squeak, it sounds like we have a mouse on board) and shifting in the rear is now flawless. No more "2 up, 1 down" shifts or delayed shifts. Everything just works.

Our next steps are to change the stoker crank size from 150 to 165 (you can see another thread for motivation), and to swap the rings. We want to stick with at least a 52 in the front because we definitely find that we can spin out on some descents around here. But we're hoping to get an easier little ring than 39 because we have some pretty monstrous sustained climbs in our area. We'll either go with the Wickwerks 53/34 (rumor has it that it's finicky to set up with eTap, so we're still debating), or a normal semi-compact (52-36). We've also (back)ordered a Digirit WiFli extender so we're hoping to install an 11-46. We were told that it might not work, in which case we'd have a 36/40 lowest gear, which we're okay with. Of course, a 36/46 granny gear would be even better, but one can't have everything...

By the way, we tried using the 30-39 ring combo instead of the 39-52 combo, but the big ring was definitely getting in the way of the derailleur. We did not try removing the big ring. It's actually something we had considered, because we had also contemplated going single-side drive and getting a smaller ring for the outboard triple (like say going 30-46-42 by swapping out the 39-52 for 46-42), but we managed to find an inexpensive set of stoker cranks so we're not too concerned anymore about swapping to single-side (our biggest concern was the added cost of tandem components, which has been mooted).


Rear WiFli derailleur with a Wolf Tooth Road Link.


2x eTap front derailleur on a triple. Only the middle and outer ring are usable. The inner ring is basically just decoration now.

eTap shifters, with a drag-brake lever on the non-drive side of the handle bars.
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Old 07-08-20, 07:49 AM
  #19  
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totally unrelated to your upgrade, but I'm so very curious about your apartment! Those are some massive support columns you've got in your living room. I'm assuming that this is a daylight apartment of some nature?
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Old 07-08-20, 07:58 AM
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Our apartment building is a converted warehouse, and we're on the first (American second) floor, so we have huge support pillars. Our neighbors a few floors above have the same pillars, but they're much smaller in diameter. Our apartment is *almost* big enough to bike in. Almost.
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Old 07-08-20, 09:56 PM
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While I recognize the frustrations of poured cement ceilings (i.e. reflects all the sound, not easy to run new wiring etc), I'm super jealous!
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Old 07-09-20, 06:54 AM
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Is there any reason that no one suggested the di2 XTR 3x FD? I am considering upgrading to electronic shifting down the road sometime after getting some miles on a new to us tandem and would want to keep the 3x crankset. I think using XTR components will be the way to go for us, and maybe using the Ultegra road brifters and the other XTR components.
One concern I had was wire length, I think some of the runs would be pushing the length on the spec sheet (1.2-1.4m). Maybe that's not too much of a concern, or maybe worth looking into the D-fly wireless module and batteries for the RD.
https://bike.shimano.com/en-EU/produ.../FD-M9050.html
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Old 07-09-20, 07:15 AM
  #23  
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You absolutely can do a 3x up front. I think it's mostly don't feel that there's good enough reason to do so however. With the new wide range 11 and or 12x cassettes in the rear, you can achieve the same gear inch ratios when running 2x up front.
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Old 07-09-20, 07:35 AM
  #24  
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Three reasons:

1) Ignorance - only after we bought our eTap groupset did we realize that one can use road-bike Di2 shifters with MTB Di2 components.
2) Internal routing - Our frame is aluminum and has ZERO internal routing. The few frame builders we could find said that it's a bad idea to drill into aluminum. And external Di2 wouldn't work well with our setup.
3) Shifting performance - A triple is still a triple and won't have as good shifting performance as a double. With the extended range we have in the back, we're perfectly happy to have a compact or semi-compact in the front. We'd contemplated going to sub compact but decided against it.
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Old 07-17-20, 08:40 AM
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Originally Posted by adamant628 View Post
Is there any reason that no one suggested the di2 XTR 3x FD? I am considering upgrading to electronic shifting down the road sometime after getting some miles on a new to us tandem and would want to keep the 3x crankset. I think using XTR components will be the way to go for us, and maybe using the Ultegra road brifters and the other XTR components.
One concern I had was wire length, I think some of the runs would be pushing the length on the spec sheet (1.2-1.4m). Maybe that's not too much of a concern, or maybe worth looking into the D-fly wireless module and batteries for the RD.
https://bike.shimano.com/en-EU/produ.../FD-M9050.html
We thought long and hard about taking that approach with our new tandem last year. In the end we didn't do it because the XTR front derailleur is limited to a 46 tooth big ring. We love our fast group rides too much for that. We went with Di2 double, 50-34 up front and then 11-34 for our road wheels and 11-42 for our gravel wheels. We find that that's plenty low gearing.

Wire length is not an issue, everything we needed was available from Shimano.
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