2,288 Comments

  1. What does the third update add to the system?

  2. What a great site! I’m running Ultegra Di2 6770 in 10-speed, but with the SM-EW90-B (the 5-port box). Steep learning curve, as I’ve just started thinking of upgrades. Any help on these questions would be much appreciated:
    1. Will SM-BCR2 (the internal battery charger) enable me to program using E-tubes?
    2. What additional benefit is the SM-PCE1?
    3. I’m thinking of “upgrading” Ultegra FD-6770 to DA FD-9070. Is there any benefit / difference?
    4. Can I run the FD-9070 with RD-6770? (I’m likely to upgrade to RD-9070 eventually)
    5. Will the SW-R600 (climbing shifter) work with that system (both 10 and 11 speed)?
    6. I had trouble with the (external) battery discharging quickly when I upgraded from SM-EW67AE to SM-EW90-B. Is that a known problem? My LBS upgraded the firmware (presumably with the SM-PCE1) and it seems to have been cured, but are there any lingering issues known?
    Many thanks in advance for any light on these.
    Bruce.

    1. 1. Will SM-BCR2 (the internal battery charger) enable me to program using E-tubes?

      Yes, if you have front junction SM EW90 A or B. This is how I programmed my 6770.

      1. Thanks Andy. I’ve found most of the other answers out by “suck it and see”:

        2. Still don’t know. Presently can’t see any need for SM-PCE1 over the SM-BCR2.
        3. Ultegra FD-6870 is smoother and quieter than FD-6770. DA FD-9070 is not discernably different to Ultegra FD-6870, except twice the price. Same speed, same smoothness, same noise level.
        4. Tried Ultegra RD-6870. Cannot imagine how DA version could be “better”.
        5. SW-R600 works fine in the system.
        6. Upgrade to the firmware seems to be the solution.

        In short, everything which runs e-tubes is inter-compatible. Unless you “need” Dura Ace written on your kit, Ultegra is as good as it gets. Save the money. Save weight by trimming your fingernails before riding.

    2. the SM-BCR2 can not do diagnostics and the SM-PCE1 can, so if there is something wrong with one of the components or the firmware did not update correctly you can’t know what’s wrong

  3. I assume the ST-6770 (10speed) only comes in the Road Bike-looking lever/brake rather than the look of the ST-6871 (more the TT lever/brake look)? Thanks!

    1. Chris yes, the only Ultegra 10 Speed shifter is the standard brake shifter- however because all of the Di2 components are interchangeable, I would assume that one could use the 6871 TT shifters provided the firmware is updated and the same.

  4. The green light on my junction box doesn’t light up when depressing the shifters, even after a full charge. Problem? I guess that as long as the red light works when it gets low thats really what is important, no?

    1. Author

      I can’t say I’ve ever noticed the green light being on or not except when charging, so I don’t consider it to be all that critical. The only concern is if there is another issue with a component or connection that is causing the issue.

    2. Yes there is a problem, thats the only way to check the battery level, something is wrong with junction box A. the RED light will not indicate battery level if the battery light is not working. Can you get it to go into RD adjust or reset mode?

  5. Great site, thanks so much for posting this. I have a 6770 10 spd and am about to order RD-6870 as well as an 11 spd chain/cassette for an upgrade to 11 spd. Can anyone confirm for sure that this is all that is needed for the upgrade. I.e.that I do not need FD-6870 and a 6800 crankset (my wheels are 10/11 spd already). There is some conflicting info on other websites that suggest that FD-6870 is needed as well and FD-6770 simply does not work when paired with RD-6870,

    1. Is there no one that has actually done the 10->11 speed upgrade and can confirm what is needed?

  6. Bjarni- I converted my Lightspeed Ci2 to the 11 speed last month. I also have a Lynskey R-255 that I built up in November that is completely 6870 including cranks, brifters and derailleurs. Yes, all you should need is the RD-6870, the CN-6800 chain, and your choice of cassette. Depending on firmware arrangements, you might possibly need to update firmware in components so they are all on the same page, but I have been using that setup for a few weeks without any real problems in shifting performance. I did not upgrade the cranks, which are FSA and while it shifts fine, it is noisier than my Lynskey which is totally setup as Shimano reccomends. The complete package does shift slightly better, but the overall the shifting is amazingly smooth on both. Th FD-6870 does shift slightly different than the FD-6770- but would be difficult to describe. It seem to push the chain all the way on to the upper or lower ring right to the limit stops, and then trims back off. I don’t notice this with the 6770, but I don’t know how that would effect shifting performance as it really doesn’t seem to make any difference.

    1. Thanks a lot for the response. My order is placed for the upgrade 🙂

  7. THANK YOU SOOOO MUCH!!! NOW I HAVE A FULL INFO !!! I’m trying to use my 6770 on my new BMC frame and like to have RD6870 to get 11 speed. Supper!!!


  8. Hello,
    I just started my Di2 carrer with an Ultegra 6770 set. I would like to use the Shimano Flight Deck Computer but I didn’t found any information if this set (with the ST-6770 levers) will work with it and if yes which cable set I need to connect the flight deck to the system. Can anybody help me with this problem?
    Many Thanks!

    1. Author

      Shimano hasn’t been clear on FlightDeck support of Di2. It was announced, then retracted, then perhaps released but with no details. As I understand it, you would need the 5-port front A-junction and it would wirelessly connect to the FlightDeck cycling computer to provide the current gear selection information.

  9. Hello,
    Today I installed a RD6870 on my bike. The rest of the system is the “old” 6770 type. Now I can’t get the RD to work, it doesn’t move. The front mech still works as it should. Do I need to upgrade the firmware on my old system to get it to “talk” to the new rear mech or what could be wrong?

    1. Author

      You definitely need to upgrade all of the component firmware versions. The Shimano software will also help with diagnostics.

    2. I too replaced the older RD6770 with the newer RD6870 on my bike and it does work fine. Yes, I did get the firmware on the 6770 upgraded first, so you will probably need to do the same.

      While the rear shifting works a treat and so does the front, I do get a little noisier drive train at the front on certain gearing. Am wondering if I need to upgrade the older 6700 chainset/crank at the front with a 6800 model to get a quieter drivetrain like previously. Other than the slight noise, it all seems to work fine and am happy with it.

      1. Does your front derailleur trim appropriately with the RD-6870?

        1. Yes it appears to be trimming well like before. Now that I’ve done a few hundred km after the upgrade, the front drive train seems quieter too. I’m guessing the new 11 speed chains needed to bed in with the front chain rings a little. I can’t say the new 11 speed made me any faster :-).. but I’m still very happy with it as I didn’t need to spend a lot for the upgrade.

          1. The FD 6770 will autotrim, but its autotriming for a 10 speed setup, thats why there is some noise with some combinations, its a useable combo, just not optimal.

  10. This is a great guide – thanks. Shimano should give you a job!

  11. Carlton…I just had my new ride built up with 6770/9070 di2, however I have an issue with the internal battery. It will not fit in the seat post or seat tube so I’d like to install it in the downtube. This can be done but removal is not easy and my mechanic said that the PC adaptor has to be connected directly to the battery for programming. I would think that all this could be accomplished through the 5-port junction box under the stem if I unplug all other devices. Am I wrong? Thanks

    1. Author

      Mark, you are correct. The external battery has to be plugged directly into the PC diagnostic tool to be updated. The internal battery does not; it can be updated as you described using the 3 or 5 port junction and the combo charger/PC tool. That’s how I updated my internal battery.

      1. This is true, however, when I updated my internal battery firmware, I was warned to disconnect the other components to avoid the possibility of the firmware update getting misapplied to the wrong component. This just meant temporarily unplugging the shifters from the upper junction block and unplugging the e-tubes at front and rear derailleurs, applying the firmware update (through the upper junction block, as normal), then plugging the components back in. Have your e-tube tool at the ready.

  12. Great blog! I’m getting a Di2 on my new bike (on order) out of curiosity how often have you been required to update the firmware?

    1. Author

      In my experience, there have been firmware updates available about every 4 months. However, I don’t think any of them are mandatory, so you don’t *have to* update it at all.

  13. Hi all – quick question ….with a new 6870 build with internal seat post battery and 3 port Junction A …..how many  EW-SD50 wires will i need ? or do you just buy a long length and ‘cut as needed’ ? im just not sure what wires/cables come with the junctions / chargers / battery etc ?

    Cheers
    Paul

    1. Hi Paul- with a 6870 build you will need 6- if using the three port junction. Personally i would opt for the 5 port, it is only a few dollars more and gives you additional shifting options should you ever choose to add some TT bars or thumb shifting. Either way, you will need one cable each for the brifters to the junction box, one cable from junction A to the rear 4 port junction, one to the battery, and then one to each derailleur. They come in various lengths, make sure to give yourself some slack when measuring. They can not be cut as they have proprietary ends on the cables.
      Arts Cycle gives a pretty good description and diagram, just remember that it shows the 6770 brifters which had a short cable already built in. The 6870 brifters do not have a cable attached hence the reason you’ll need to get two.

      http://blog.artscyclery.com/ask-a-mechanic/ask-a-mechanic-di2-wiring-and-another-bottom-bracket-question/

      1. Thanks mate – thats great ! …the Arts Cyclery diagram illustrates EW-ED50 cables ….can i safely assume EW-SD50’s are the same thing ….just get 6 in the correct lengths ?

        cheers again!

        Paul

      2. Also ….what would typical lengths be for a ‘standard’ 54cm TT road bike …Drop bars ….non TT etc ….for each –

        1 x Left shifter to junction A
        1 x Right shifter to junction A
        1 x Junction A to Junction B @ BB
        1 x Battery up seatpost
        1 x Rear D
        1 x Front D

        Cheers again!!

  14. Handy stuff here. Does anyone know if the SM-BCR2 USB Charger will charge an external battery SM-BTR1 so not needing old style SM-BCR1 charger? Not sure I can find anything definitive…

  15. If anyone is interested in upgrading a 6770 setup to a seatpost battery but want to use the This SM-EW67A front harness and not pay all that extra money for new shifter wires and 3or5 port EW90A junction box + charger, you can buy a seatpost battery kit on eBay including a charger that will allow you to charge through the harness via, shifter port. http://www.ebay.com/itm/301014528309?ssPageName=STRK:MESELX:IT&_trksid=p3984.m1555.l2649.
    You can also buy one for a 7970 setup including an EW7975 internal harness, or just the battery cable to plug into the EW7975 harness. You can also contact me direct via email Di2diy@gmail.com

  16. Hi all, another quick Q for u pls, thanks in advance ….

    DA9000 Crank, chainrings, chain and cassette….be ok with 6870 FD & RD ? ( will also be running 6870 shifters ) ….?

    Thanks again!

    Paul

  17. CHAINRINGS??

    If not using Shimano crankset, which chainrings are folks using for the 11-speed setup? Having any problems?

    Thanks all.

  18. Author

    Mark / Paul: The biggest concern with front chain rings and Di2 is the rigidity. You want the larger front ring to be as strong as possible to resist flexing against the higher forces of the front derailleur. Having said that, any front chain ring should work, just a with perhaps a little more hesitation. If you’re using non-Shimano cranks/rings, I suggest PraxisWorks; they are forged for additional strength and have very good shift ramps.

    1. Hi Carlton ….thanks again ….i was more just looking for confirmation of my current set-up …

      with the following existing set up:

      DA9000 Crank,
      DA9000 Chainrings,50/34
      DA9000 Chain
      DA9000 cassette 11/28

      Will it be ok to use an Ultegra 6870 FD & RD ….( will also be running 6870 shifters ) ….?

      Thanks again!

        1. Music to my ears …thanks again Carlton ….and can i assume this setup will work at least as good as it does with the full 6800 drive train ? (albeit lighter) ….but functionally …as good ….

          Cheers again!!!! Much appreciated

    2. Carlton…I ended up using Specialties TA chainrings and am having trouble going from the 36 to the 50. It doesn’t want to lift it at all. After buying these (super light) rings I realized that they were 10-speed. And in hindsight, I’m not sure they are not Campy.

  19. First, thank you for such a good review and description of all the components!

    1) I was wondering if it is possible to configure the Dura Ace rear derailleur (RD-9770) to work with a 10 speed cassette. Some places, I read yes and others say no.

    2) What type of programming is done when connecting a PC ? Is the software easily available ?

    3) I am thinking of using the internal battery SM-BTR2 in my 2011 Trek Madone 6.9 SSL. Trek says it is fine. I am curious, does the SM-JC41 get installed Inside the frame through the bottom bracket hole ?

    Thanks

    1. No, RD 9070 is 11 speed only, there is no firmware hack or e tube option to make it 10 speed. However you could use the limit screw to lock out the 11th cog, the spacing between 10 and 11 speed is vary close to the same, it will shift ok but not perfect in all positions

  20. Can I replace a B junction box (SM-JC40) with an A junction box (SM-EW90-A) while leaving my existing A junction box (SM-EW67-A-E) at the bars. To enable the use of the internal battery? I want to keep the SM-EW67-A-E up front because it is smaller and fits perfectly inside my stem.
    Thanks

    1. No, you can only have one A box, besides if you put the EW90 in the frame how will you charge the battery, it charges through the EW90. However there is a kit on eBay that you can install and keep the EW67, it plugs into the JC40 after removing the current battery it comes with a charger that will allow you to charge the seat post battery through the open port of the shift lever, or the RD cable with a JC40 box, look for Di2 SEAT POST BATTERY KIT FOR ULTEGRA 6770,6870 or Dura Ace 9070, FITS 27.2.

  21. 1) What type of programming is done when connecting a PC ? Is the software easily available ?

    2) I am thinking of using the internal battery SM-BTR2 in my 2011 Trek Madone 6.9 SSL. Trek says it is fine. I am curious, does the SM-JC41 get installed Inside the frame through the bottom bracket hole ?

    1. (Pierre, this information in already posted here above)
      SM-PCE1: This PC Configuration and Diagnostics adapter will not charge the internal battery. It offers the same configuration options as the SM-BCR2, but also add some advanced diagnostic and troubleshooting features that the SM-BCR2 does not have. It attaches to via the standard E-tube wire (just like the EW-SD50 cables) rather than to a dedicated port on the side of the front A junction.
      shimano_SM-PCE1_overview

      Shimano E-tube Project Windows PC Software: This free software is used to update the firmware of all components. It also can be used to change the configuration of each shift button / lever (any can be programmed to upshift or downshift either the front or the rear derailleur.) It can also be used to enable multi-shift, where the shifter is held and the rear derailleur shifts through multiple gears until the shifter is released. The speed of the gear changes during multi-shifting can also be configured. The software is available from http://e-tubeproject.shimano.com/.

      I have found its much easier to pull the crank on the trek to do the internal install, puttin the JC41 through the hole for the battery mount is doable but routing all the wires and connecting it all is tough, just pull the crank and save yourself from the hassle.

      1. Thank you for the detailed answer and sorry I didn’t notice the détails on the programming above. I’ve exchanged multiple e-mails with Trek because they keep on only answering the first question of a multi-question (numbered!) e-mail… Just been a bit of a frustrating day… 🙂

        You confirmed that I should simply pull the crank and run all the wires and junction box the easy way. Thanks !!!

  22. Thanks for the great review. When I called Shimano today to discuss 11 Speed upgrade of my Ultegra 10 Speed Di2 they claimed that I would need to replace my front derailleur in addition to my rear derailleur as the “brain” for the system is now located inside each of the individual derailleurs, has that been your experience or are they just trying to upsell me?

    1. The 6770 FD will work with the 9070, 6870 11 speed RD but it will be auto trimming for a 10 speed setup. Depends on the chainring and cassette combo on how much of a difference it will make, but as long as you don’t ride with max cross over i.e 39×11 or 53×28 it will be fine.

      1. I was planning on 50-34 compact crankset with 32-11 cassette for maximum flexibility during RAAM

        1. Well like I said just don’t run a bad chain line and you will probely not notice any difference.

  23. Hi Carlton,
    Thanks for sharing this info.
    I have one query though…
    I want to set my Time Trial bike up with Di2 and was wondering if the following is possible.
    Can I link up the rear Ultegra 6770 and front Ultegra 6770 mechs with a 3 port SW-EW90 connected to SW-R671 shifters only?
    I dont want the expense of buying ST-6871 levers so hoped the TT shifters would do what’s needed on their own. I assume the ‘brain’ of the shifting is in the SM-EW90 junction box?

    Any advice/ help will be greatly appreciated.

    Thanks again

    Alan Hall

  24. If you were going to buy a bike and you had two choices. One being Dura-Ace Di2 and one being Ultegra Di2 and there was $1000 difference what would you buy. It is for a TRI bike both being 11 speed

    1. Is everything else on the bike identical? I would probably base my decision on more than just groupset but for $1000 saving I would personally go Ultegra every time.

    2. Author

      I agree, would definitely go Ultegra. The $/gram cost is pretty high, and the performance and weight differences are very low.

      1. Everything is basically the same. All the brake system is Ultegra or Dura-Ace depending on bike. The handle bars are Oval 950 on Ultegra bike and Oval 960 on Dura-ace

  25. Hi,
    after a crash, my Dura-ace Di2 system got blocked. The battery has charge, and when I use the button bellow the 3-port junction, the derailleur works, but the problem is that none of the shifters work. There seams to be a disconnection between the shifters and the 3-port junction. Any advice on that problem?
    Thanks in advance

    1. Author

      Using the PC Diagnostic tool would be my first suggestion. If you don’t have that, disconnect all shifters and then connect each one at a time to see if you can isolate the problem or find an isolated problem.

      1. Thanks a lot Carlton, I hope i can find a PC Diagnostic tool in Ecuador !!! I really doubt it. Anyway, thanks for your great community help trough this page!

  26. Would it be possible to take the switches and connectors out of ultegra 6770 levers and put them in dura ace 7970 levers. I actually prefer the look of the 7970 levers to 9070. That way I get E tube wires into 7970 levers, Bingo!

    1. Author

      Gav, it wouldn’t be a direct swap of parts. The electronics and levers are shaped differently between the two. I wouldn’t recommend it as it would be a huge amount of work with lots of customization. But I guess with enough time, effort, machining, and electronics skills, anything is possible.

  27. Great site! sharing with all my cycling buddies. Question: Can the external SM-BTR1 battery be left on the SM-BMR1 External Battery Mount and still be charged with the SM-BCR2 connected to the EW90-AB?

    1. I just need confirmation this has been tested to work or not work. but according to Competitive Cyclist it does.

      Quoted from Competitive Cyclist:

      The charger is made to accommodate both internal or external battery systems by connecting to the SM-EW90 junction box.

      1. Author

        I can’t say for certain, but it was my understanding that the external battery could not be charged this way as it did not have the necessary charge-limiting circuitry inside.

  28. Hi Carlton,

    Great info source – congratulations – and well done on sharing it with everyone. Can I ask a short and (apologies in advance) possibly stupid question. Can you use 6870 electronic shifters with 6800 mechanical derailleurs? I have a mechanical group and was looking to maybe purchase electronic shifters to replace a shifter with cosmetic damage with a view to upgrading to Di2 in stages.

    Can you let me know if known or perhaps direct me to a source that can confirm either way please?

    Thanks in advance.
    Dave

    1. Not possible! Except for the brakes, but no shifting.

  29. For the pce1, did you have to download other software besides the etube software to get it to work? I plugged my pce1 after downloading etube and it does nothing.

    1. Hi, a secondhand frame I’ve bought comes with old dura ace wiring including battery and external mount. I’m moving to new di2. I can keep the battery but what about the mount? I think not as the 4 wire cable is an integral part of the mount. Can some one confirm? Thanks Dave

      1. It can not be used with e tube system.

    2. Author

      Mike, yes, all you need is the SM-PCE1 and the free etube software from Shimano. Make sure the USB device driver initializes properly in windows and make sure there is battery power to the components you’re upgrading.

  30. I just got the parts to upgrade from 10 speed Ultegra Di2 to 11 speed, will be replacing crankset (with DurAce), chain, and 11 speed medium cage Ultegra RD to accept Ultegra 11/32 cassette. When I swap 10 speed RD with 11 speed, is it “Plug & Play” or do I need to do some sort of firmware or programming update?

    Thanks

    1. Author

      Gary, it’s hard to say if you need to do anything or not because it depends on which version of firmware your existing components have. If it works and you’re happy with it, no upgrade required. But for the highest level of compatibility/reliability, I’d recommend making sure everything has the latest firmware version.

  31. Carlton,

    My DA9070 set up is playing up, shifting started to be hesitant (shifting would happen 1 sec after pressing the shifter) and now its not working at all unless I keep my finger pressed on the shifter for 30+ secs!! (with full batt)

    In addition to this the green ‘charged’ light comes on of its own accord every now and then.

    I have the E tube software package and the SM-BCR2 connector but it will not allow me to make a connection, it charges but will not connect to e tube.

    Pulled all the cables & reconnected, reckon it must be a bug. You heard of anything like this before?

    1. Author

      John, that’s not normal. You have a bad component or connection somewhere.

  32. My LBS was upgrading my Ultegra 10 Di2 to 11 speed. I’m keeping the existing FD and swapped the crankset for a DurAce 11 speed. The FD works fine but the RD does not seem to respond in anyway to the shift key on the brifter. The green light comes on when you hold down the button but it does not seem to send any info to the RD. They double checked all electrical connections but it sill does not work, any suggestions?

    1. Thanks Carlton, I had LBS with programmer update firmware and she seems to shift perfectly. If you recall, I only swapped the RD for 11 speed and left the FD alone yet it seems fine. I will take out on a long ride with some steep climbs tomorrow to see how it works in the real world.

  33. Thanks you so much for putting this together. Your site is awesome. I was hoping you might help me with an issue please. I just installed a 6870 RD on my 6770 bike. The derailleur won’t work at all. I’ve tried re-connecting the cable several times to no avail. I then connect my old 6770 RD and it works fine. Any ideas would be appreciated. Thanks!

    1. Have you updated the firmware???, if not it will not work.

  34. Hi Carlton, wow that’s comprehensive I just wondered whether you had any idea about the possibility of using the Hydraulic DI2 levers with the Alfine rear hub gear? It seems bonkers that it isn’t a stock option although I’m sure it will be very quickly.

    1. Author

      As far as I know, the Alfine BL-S705 levers send the same command signals as the R785 hydraulic shift/brake levers, so they should be able to be used together, but I haven’t seen it myself so I’m not 100% positive.

      I agree, that combo has to be coming very soon from Shimano.

  35. Ah right great I thought I hadn’t imagined that from what you’d written I feel slightly less silly. Thanks again, time to get out the credit card ;0)

  36. gents….all this information is doing my head in. i am a user of the 7970 DI2. bought it second hand not long ago. it worked just as advertised until just recently the RD has been shifting without provocation. all rides have been in the dry. have run through the set up on numerous occasions only to get the ghost shifting come back. the LBS isn’t that local. what would the next step be that I should be looking into….is the diagnostic tool going to help with this
    cheers

    1. Author

      Marc, my guess is that that the tool will not help. The design of the original Di2 system is much more prone to shorts (to ground/with other wire) causing a shift. You most likely need a new harness. I’m assuming that it is always an upshift or a downshift, not both. That would tell you which wire to isolate.

      There is also the possibility that it is a mechanical problem, and not electrical at all. It could be that the internals of the rear derailleur have worn to the point that it is not holding position properly. In this case, a new rear derailleur (or possibly a new spring kit?) would be required.

    2. I would also suggest that the RD Servo is going bad, I have seen this several times, starts ghost shifting than will just stop shifting all together. However it also could be the rear harness. A couple of questions; is the wiring internal or external? if internal did you use the shrink sleeve on the connectors when you installed the harness? often times people who install a use harness (EW7975) do not use the proper shrink sleeve (adhesive lined) and just tape the connectors with electrical tape, than the connectors are not waterproof… you would be surprised just how much moisture is inside a carbon frame after just one ride in a light rain, or washing. Also sometimes using a used EW7975 harness can be an issue, depending on how much care was exercised when it was removed. I do custom retrofits on non Di2 specific frames and build custom seatpost harness kits for both e tube & 7970. I have found the 7975 harness to be quite hardy, but they can be damaged if uninstalled by gorilla bike mechanics. If you can get another harness like an external, and install it temporarily to see if it still acts up, it will answer the question of bad RD or harness. I have several external harnesses, and could work something out if you are willing to pay shipping cost. contact me at Di2diy at gmail.com

  37. I would also suggest that the RD Servo is going bad, I have seen this several times, starts ghost shifting than will just stop shifting all together. However it also could be the rear harness. A couple of questions; is the wiring internal or external? if internal did you use the shrink sleeve on the connectors when you installed the harness? often times people who install a use harness (EW7975) do not use the proper shrink sleeve (adhesive lined) and just tape the connectors with electrical tape, than the connectors are not waterproof… you would be surprised just how much moisture is inside a carbon frame after just one ride in a light rain, or washing. Also sometimes using a used EW7975 harness can be an issue, depending on how much care was exercised when it was removed. I do custom retrofits on non Di2 specific frames and build custom seatpost harness kits for both e tube & 7970. I have found the 7975 harness to be quite hardy, but they can be damaged if uninstalled by gorilla bike mechanics. If you can get another harness like an external, and install it temporarily to see if it still acts up, it will answer the question of bad RD or harness. I have several external harnesses, and could work something out if you are willing to pay shipping cost. contact me at Di2diy at gmail.com

  38. Wondering if anyone could help with a problem trying to update the Di2 firmware using E-Tube Project ver 2.5.0 . When I click on “Connection check”, it tells me that the following units are connected:
    SM-EW90-A
    ST-9070-L
    FD-9070
    ST-9070-R
    RD-9070
    and that a firmware update is available for SM-BTR2. But after clicking “Next”, it just keeps going around in circles, going back to “Unit recognition”.

    In the main menu, the buttons for “Customize”, “Error Check” and Update firmware” remain grayed out. Still available are: “Connection check”, “Preset” and “Change bike type”.

    Thanks for any help.

    1. Try disconnecting everything but the battery and update just that one component. If that doesn’t work, try connecting directly from the A junction to the battery with no extra junctions/connectors/wires in between.

      1. Thanks for the info. I also have this going in parallel with my LBS, which is trying to contact Shimano for an answer. I can suggest your solution to them.

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