1. Still experiencing a delayed shift issue with my Ultegra di2 FD.
    Question: Do I adjust (1/8th turn at a time) the screw marked LO or H?
    Yes, I have gone by-the-book to: a) complete procedure for Adjustment Mode for both RD as well as FD – using lighted button of Junction Box A and b) ensured chain rides awfully close to inner walls of FD. Perplexed. Help. Thanks.

    1. The mechanical adjustments have nothing to do with shift speed. You should check to see what the shift speed settings are in the customization settings, perhaps they are set to “slow”

  2. Recently bought new 6870 FD + RD, 3 port JB, internal battery and going to use 6770 shifters. Plugged everything in on workbench and it worked fine. Thought I would make sure everything was updated and running the latest firmware so connected it up to etube and it started updating components but then the SM-PCE1 PC Interface Device fell off the bench and the cable unplugged and now etube won’t recognise the FD and FD now won’t work.

    Tried updating the firmware of FD individually and also while connected to the other components. Checked all the cables and they are securely connected. Connected another 6870 FD and it works fine so it looks like there is now some kind of fault with my FD, is there any way of fixing it?

  3. Hi Carlton, I have a 7970 set up with a 53/39 chainring. I have searched but cannot find anything about what it would entail if I were to change this to a 52/36 or a 50/34. Any help is appreciated.

    1. there in no such thing as a 7970 crank, so searching under that part number will find nothing, also there is no such combination of 52X36, and to have a compact 50×34 you need a different crank arm 7950

      Model number FC-7900 130 mm
      Front chainwheel FC-7900
      A-53/42T, B-53/39T,
      52/39T, 54/42T,
      55/42T, 56/44T

      FC-7950 110 mm
      Front chainwheel
      Technical Service Instructions SI-1KY0A-002

      43.5 mm

      Crank arm length 165, 167.5, 170, 172.5, 175, 177.5, 180 mm

        1. There is most defently NOT a 52×36 for a FC7900, yes for the newer FC9000/6800.
          Read and understand before you dispute.

          1. Apologies for questioning you, but if a guy wanted a mid-compact on a 7900, he could piece it together. In my limited interwebs searching I have seen a 7900 52T and 36T for sale separately, but not in a set.

          2. A non Shimano 36 will work but will shift for shit as the inner and outer need to be matched A, B, E 52X36 is non standard. No apologies necessary

          3. Search tricks you into thinking you’ve found a 36t for a 7900 when in fact, its for a 7950. Apparently Praxis makes it for the 7900 but I haven’t looked into it.

      1. Thanks di2diy, I think I know what I meant to say. But just made assumptions. I have a 7900 at present.

        Back onto my intended question, can I change to a compact 7950 without compromising the di2 setup? Or will I need to change any specific parts?

        Also, are there any mid-compact setups I can use with my current 7900 di2 setup?

        Thanks in advance. Much appreciated.

        1. If you go to a 7950 compact you will meet to lower the FD, but it will work. If you want to use mid to compact rings and be able to change just the rings buy a FC 9000, that will allow you to change to several combinations.

        2. It may be cheaper to buy a new 9000 crank as Di2diy has suggested, or you can piece it together. I found a 7900 52t on amazon and the 36t is available on a lot of on-line retailers if you search. Maybe your lbs can get them also.

          1. Definately found a 52t, but not a 36t so never mind. So Di2diy said, the 36t is available on the 7950.

          2. If you go with a non Shimano ring the timing for the pickups will be off and it will shift for shit. The FC9000 is the best solution.

          3. Could someone please expand/clarify/explain the phrase “If you go with a non Shimano ring the timing for the pickups will be off” – extracted from a recent post. What timing and what is pickups? I ask because it may be pertinent to my issue. Thanks

          4. in short without trying to cover all the combinations… Shimano chainrings have a letter designation (type) for their rings, its has to do two things, the ramps/pickups and the locations for inner and outer teeth relationship (timing)… non shimano rings normally do not. For example FC7900 53×39 are both B, you can change the 53 to a 54 but its an E, and wont shift as well with the 39 as the ramps from the inner will line up differently, for a FC7950 50X34 both are F (also a different BC), the letters specify the timing for the ramps and teeth and its important to try and match the type for the best shifting. For the newer cranks series FC9000/6800 there are two letters for the type, for a 52X36 they are both MB for a 50X34 they are MA, 53X39 are MD, so when changing rings its important to pay attention to the type “letter” for the combinations. After market rings (non-shimano) can be used and did not make a big difference until Shimano released their 7900 cranks and made it possible to shift under full power, but on 7900 & 9000 series cranks it matters, mismatched rings will not shift as well under power and can throw/drop the chain. I know some people do ride different aftermarket rings including rotor/elliptical and seem not to complain, at least not out loud.

            I have built a number of bike over the years and found that Shimano have it right when it come to making the best shifting crank-sets… when used as directed.

  4. Have a bike with Ultegra 10 speed Di2 that will no longer shift. Was working fine, placed in storage for about 6 months. Checked it every other month and the derailleurs moved when the shifter was pressed. Then the battery lost charge. I just recharged the battery but now the system will not shift, front or rear. Tried the battery in another system, works fine, no shift issues. Took the battery from second bike, installed in first bike that will not shift and it continues to not shift. Conclusion – not a power/battery issue. Checked all connections, reseated the cable connectors using the tool, got the audible click when connectors were plugged in. Still no shift. Tried crash recovery mode, lights on junction box are correct but still no shifting. Any suggestions?

    1. Hi John,
      I had the same problem with my Ultegra !! speed Di2 setup. You could’t try to do a reset of you derailleur by pressing the the little button on the junctionbox for 5 seconds.
      That solved my problem.
      I think when you want to test you system once per month you realy have to rotate you cranck so you do have a real shift of your RD.

      1. John Q,
        be sure to remove the rear wheel when doing this reset so the RD can go through all the gears. Although I’m not sure this will fix the issue, its possible that the RD is in crash mode because you did not actually shift the RD and its jammed the servo.

        1. Thanks for the suggestions but the issue persist. It will go into crash recovery mode but with or without the rear wheel, the RD will still not move. Nor will the FD.

          1. I suspect the front junction. Do you have another bike with 6770 components you can test the FD/RD with?

          2. I was able to obtain the diagnostic tool sold by Shimano. I ran all the connection test and confirmed that the battery/connection, upper junction box, shifters, and both derailleurs are functioning properly. Each of the test is run with a direct connection, not through the lower junction box. The test narrow the problem down to the lower junction box or both wires that run from the box to the FD/RD. Not likely that both wires are bad. The Trek Madone 5.2 has a reputation for eating up BB bearings, mostly water damage on this bike. I found moisture in the BB shell, around the bearings, and the grease was obviously water contaminated. I plan to get a lower junction box and retest. The box does not show corrosion but it’s a part that I can borrow and test with. Nothing to lose.

          3. Sounds like you got it. I have found its hit and mis with the PCE1, some times it doesn’t find a fault even though there is a problem. If you were to try drying out the junction box wit a heat gun or a hair dryer you may be able to get the water out, clean out the ports wit a qtip and some alcohol, you may be able to get it to work. It’s also possible that the connectors were not seated completely and let water in. I have never had a JC 41 go bad but I guess it could happen.

  5. I have an earlyish Ultegra Di2 system (about 10/2012) and have never updated any firmware/software on the system so I’m not sure which firmware its using but it must be early 🙂 I have bought a replacement rear derailleur RD6870 because I believed that with chain and cassette change I could replace my slightly creaky RD6770 10 speed unit. However the RD6870 refuses to be seen either with or without the FD6770 front mech connected. Is this solely a firmware issue with the rear mech or is it possible that the firmware in the rest of the system is simply too old? (ST6770 levers, SM-EW67 A Junction, Don’t know “B”Junction, SMBMR 1 Battery Mount and SM BTR 1 External Battery, FD6770 Front, would like RD6870 to work on rear)

    1. So the short answer is yes it’s a firmware issue, but when you update the firmware the FD6770 will not work with the RD6870. To make your life easier buy a new FD6870, and if you buy from a LBS I’m sure they would be happy to update the system for you.

      1. I was assuming that due to the age of my system it would be running firmware 2.5.0 or earlier as it has never been updated and therefore it would be capable of running FD6770/RD6870, silly ass – umption by me, what concerned me was that the 6870 didn’t even get recognised with the FD6770 disconnected so the firmware on mine must be about 1.0.0 🙂 Anyway rather than faff about I’ve gone for a complete upgrade FD6870, Int battery and SM EW90 Ajunction as well as a couple or three new wires, then with the SM BCR2 I can do my own “fine tuning” of the system, I’ll repost when it is all flying. Thanks

        1. That’s the best choice in the long run, I know some have done the limited update to make it work with the 6770 FD but that is just for those who want to save a few bucks, and it’s really a wise man who spends the money to enjoy to the fullest. Happy New gear.

  6. Carlton- have you ever taken a non-working RD-7970 apart to see what makes it tick – I picked one up for free just to test my DIY skills – It doesn’t react when you attempt a shift but it does react …slightly … when you initially plug the harness in to it- I have it apart down to the potted printed circuit board with motor and output driveshaft – next I will split the motor casing apart-can’t find anyone who has posted anything about attempting this-

    1. Isn’t that how Bill Gates started out by splitting PC-DOS 🙂 ?

    2. Pics please. Related, here’s the board of a 2015 SW-R600 shifter, after some soldering (ie. if inline images show up). Self-fusing tape added for protection and put inside handlebar. Works a charm, for shifting with a RD-6800.

        1. What Di2 levers is this plugged into?

          1. Plugs into a JC-41 in my case. Buttons (by Cateye) in pic shifts RD only and goes on the base bar of a tri bike, just behind the brake levers, one on each side. Works just as a SW-R600 obviously, ie. can be programmed as needed. Have regular tri shifters at end of aerobar extensions also, for FD and RD, but those are completely independent of this.

  7. I wonder what is “Top position electrical adjustment” in Shimano manual for? I cannot get the gap between 0.5-1.0mm, it stops moving around 2mm. Is there something wrong?

  8. I am considering fitting Di2 to my replaced frame Tandem, are there any areas I should be looking at , or is it a non starter and I should stay with mechanical. Happy to replace the group set ( well not happy but resigned that it may be necessary !) any advice would be grateful.

    1. Go with the ultegra 6870 11 speed. Long cage RD if going biger than 28 in the rear.

  9. Hey,

    quick question for you. I recently bought a set of 6870 shifters and the rest of the gear is 6770, I’ve plugged everything in and set it up but nothing happens upon pressing the shifters. Do I need to update the firmware to make the shifters work with the rest of the system or will that setup not work on my bike?!


    1. You will need to updat the firmware.

  10. hope you can help. Have a problem with my Ultegra DI2 10 speed system. Previously had problem with external battery mount and got it changed, everything fine for a while, recently system dead again, so I thought change battery mount again, still no fix. read internet found could be problem with A junction. just changed that and inserted battery, system went green – me thinking on to a winner …but no. Try to change gear nothing. Thought that it might be in crash mode. press button and red light flashes turn pedals and it goes through gears ok. at end try to change gear again – nothing. Charge battery, do same again with same results. when I press any gear change button I get no indication of battery life (i.e. green or red light) but do get red light when pressing junction A button for micro adjust of put into crash recovery. getting me frustrated… also checked all connections are good

    1. When you place a new component I think you have to do a system update.

    2. If it’s any help Malcolm, I know the connecter was working ok on my system less than two weeks ago – you bought it from me! If the crash mode is working then the junction box is connected ok to the rest of the system and the problem would appear to be from the junction box back to the levers or the levers themselves, no green battery indication on holding down a changer button would seem to confirm this – I checked this on mine just before swapping to 11 speed so I know the junction box recognises the signal. Possibilities are 1, the connecters aren’t in properly – check them again, which lever holes are they in, I’m fairly certain mine were in the bottom connection, 2. the wires have been damaged but this is unlikely as you sound quite aufait with Di2 or 3. the levers/switches are damaged a bit unlikely for both to go together. I used 6770 levers on my system with really old firmware and there is a possibility that the EW67 junction box may need updating with newer firmware if your system is less than 3 years old.

      1. Thanks for that Andrew (and the junction box). I agree that its unlikely that both shifters are goosed at the same time!!! I did make sure that the wires were seated correctly as got the “click” , but again I think they are in the top holes of the shifters (where the originals were), never thought about moving them. Again I would also think that the front mech would have worked at least.

  11. Just a thought about anything electrical exhibiting intermittent problems:
    Check (bench-test) continuity of each wire. Wiggle the wire while Ohmmeter prongs are attached to each end. This, to catch invisible, internal breaks in conductor.

  12. Ok got another question, can you use the three port A junction (EW-90A) with the external battery set up. I.E. if I change out the old style A junction (EW67) and replace it with the 3 port along with two cables to the shifters, would it work?. The main reason is that the Ultegra system is on my training bike and I have another which has full 11 speed Dura ace with the internal battery. That way I can connect my existing cable for firmware upgrades etc without needing to spend the £160 for the PCE1 tool
    Cheers guys

    1. Last weekend I removed the EW67 and replaced it with the 5-port A box on mt external battery 11 speed Ultegra setup. I do have the PCE1 tool but I don’t think it did any firmware updating when I plugged everything in.

  13. I have a 2013 Specialized Roubaix with 10-Speed Ultegra Di2 6770 and an externally mounted battery. My LBS has complied with all of the Shimano software/firmware updates. Is my system compatible with the Shimano D-fly accessory? I would like to pair it to my new Garmin 520 if possible. Also is my 10-Speed Ultegra 6770 Di2 system the same as what Garmin refers to as 6770 E-tube or are they apples and oranges? Thank you very much!

    1. Author

      Yes it compatible. You need to add the Ant+ broadcast module. And yes, your 6770 Di2 is the E-tube version. (The original Di2 was not e-tube.)

      1. Thanks for getting right back to me! Is the Ant+ Broadcast module you mentioned, the same as the Shimano D-fly accessory?

  14. i have bought a cube lightning 2016 with full ultegra di2 internal cable. Then my mechanic swapped all the group set not the (cable) to my bianchi oltre with dura ace 9070 external cable. The new ultegra 2016 shifter does not work with the old dura ace 9070 external battery cable system. But the old Dura ace 9070 shifters works on the new internal cable ultegra system. Can you please give me some advice. Thanks.

      1. my mechanic already updated the firmware of the dura ace 9070 external battery system. But still the new ultegra shifters with internal battery seat post does not work. But if we put back the Dura ace shifters to old 9070 external cable system in combination of the new ultegra di2 components it works perfectly.

        1. Update the whole system including the shifters.

        2. carl,
          Update the shifters [as Di2diy advises] and the system together.
          Don’t know why your ‘mechanic’ did not update everything on the bike and return it good to go.

  15. So looking at building a CX bike with Ultegra Di2 (ST-R785, RD-6870-GS). Just looking for a 1×11 set-up so no front derailleur. Would rather do a 1×10 but can’t seem to find a shifter hydraulic set for that. What additional components would I need to complete the setup?

  16. My prior set up was Ultegra 6870 with external battery. I just installed my 6870 derailleurs/shifters with SM-BTR2 internal battery and EW90-B junction box. I updated firmware for older components. Shifting/charging work ok. Issue I have is battery indicator light does not function when I push shifter. Troubleshooting ideas or suggestions?

  17. Hi
    Can I run just the rear DA 9070 rear mech and gear change unit with a single TT chainring set up? I Do not require the front mech or gear change unit.

    Many Thanks


  18. Will a 10 speed 105 crankset shift properly as the ultegra and dura ace?

    1. All things being equal, the 105 is a good crankset. It should shift smoothly.

      It does differ, obviously, from the Ultegra [currently my component level of choice with Shimano ] and Dura Ace [ I do have some DA components as well ].

      Much of the marketing between 105, Ultegra and DA components is about weight and much of it negligible. I do run a Di2 Ultegra ‘long cage’ RD with DA FD and other components for my hilly rides. I use the long cage to keep the large cassette happy on the back.

      105 is good, Ultegra is better, Dura Ace unnecessary for most riders, IMV.

  19. My Ultegra 6870 Di2 shifts badly since a service at my Local Bike Shop (LBS); rear derailleur hesitant to shift & sometimes downright reluctant. Mechanic at LBS rode bike, says shifting crisply & problem when I ride could be because I weigh only 66kg and he’s considerably heavier. He says lighter body weight can make shifting slower. Sounds like garbage to me; what do you think?

    1. Mate, use another Mechanic in the future. Meanwhile, take it back. That system should be super smooth and almost noiseless. It could be various things but if you have paid the guy to do a job then make sure he does it.
      If the result is poor come back to the team here; the issue will be sorted, I’m sure.

  20. I bought a new bike that had the a RD-6870-ss and an 11-28 cassette. I swapped out the RD with a GS and changed the cassette to a 11-32. I’ve followed the manual for adjusting the RD. I’ve maxed out the outboard adjustment, but I’m still getting a small amount of rub on the inside (meaning it rubs on the larger cassette). Do I need a spacer between the hanger and the RD?

    1. You don’t say what bike you have. However, assuming your drivetrain is all 11-speed you should no issues with the set up.

      Follow the Shimano set up manual slavishly and you should be good to go.

      Make sure you set up the mechanical side [B-tension adjustment bolt] of things BEFORE you set up your Di2 adjustment for the GS cage. Also, make sure you have torqued the RD to the hanger correctly without any fouling and at the proper torque [8.0 – 10.0 N·m / 70 – 87 in. lbs].

      NO SPACER on the 11-speed cassette.

      It is rare, and you should not need it, but I have come across guys having hanger issues and overcoming this with a longer B-tension adjustment bolt bought from their local LBS or a stainless steel equivalent from their local hardware store.
      You can eyeball the upper guide jockey to see if you have the recommended clearance [2-3mm].

      I say again, if you are following the manual you should have no Di2 problems. Di2 Roks.

      Hope this helps.

      1. I’ll run through the setup again. It’s a Specialized Roubaix if that matters at all.

  21. i have di2 ultegra shifter & d-fly wireless & 5 porth junction box and the garmin 810 detecte gear is good , right & left shifter button on top no scroll page left or right what this problems please let me know

  22. I have a 6770 10 speed groupset but the rear derailleur is broken. I have put a 6870rd and a fd-9070 but neither work i.e. no life. I have upgraded the cassette , chain crank to 11 speed. Do I need to upgrade the shifters and the 3 port junction as well?

    1. Author

      Phil, your answer is clearly described in the article above. You need to upgrade the firmware.

  23. I recently updated a battery&mount to latest version along with 6870 group….all works fine. Took same battery/mount and plugged into a 6770 group that has not been updated(and that group may or may not be on all same versions)and things don’t work right with that battery/mount but DO work fine with existing non updated batt/mount…..is this normal? No mash ups here so is there any reason NOT to update all things to latest versions?

    BTW thanks for helpful site!

    1. Author

      You should update all of your components to the latest firmware. If you ever want to upgrade your 6770 to 11-speed, replace both the front and rear derailleurs (and the rear cassette, etc.) It’s pretty much impossible to do a rear derailleur-only upgrade to 11-speed any longer due to everything coming with new firmware — that would have been the only reason not to update firmware, and it’s no longer an option.

  24. Firstly, thank you so much for all the information on Di2 and how to upgrade! Well done. I’m looking to upgrade my Ultegra Di2 6770 system to the Ultegra Di2 6870 with GS RD to get a little extra gearing for hilly rides. I think I understand that to do so, I just need to switch out the RD, FD, chain and cassette, but will my existing Ultregra 6750 Compact crankset (50/34) still be compatible, or do I need to switch that out as well. I’m still investigating whether my existing wheels will take an 11-speed cassette, or if I can change the free hub as well.


    1. Harris, Shimano do not advise mixing your existing 6750 crankset with upgraded 6850 RD/FD. This can be done in an emergency if you want to FORCE 10-speed and 11-speed dynamics but mixing 10-speed with 11-speed geometry chain-gates, pickup dynamics etc., will give you issues. Ultegra is a great drivetrain and the GS will enable you to run a 32t cassette. Mixing some 10 and 11 speed components is possible if you like noise, excessive wear, and an all round miserable experience.

      Advice? Swap out your crankset for the 11-speed Ultegra.

      NOTE: There is a some difference in gear-change-experience when running an 11/23t cassette compared to, say, a 12-25t. However, you will climb like never before when running the big ring on the back with a compact crankset on the front.

      NOTE 2: Keep in mind that descending with a compact might find you ‘spinning out’ due to the smaller front rings [compact]. Perhaps, a semi-compact would be a better choice unless you are climbing +12% hills. This is particularly so if you are needing to upgrade your crankset anyhow. Also, as you are needing to upgrade your crankset, give some thought to the arm length. Make sure you do not go too small and loose leverage or too long and so punch your gut with your knees or knock your bars on big hills or increase dead spot bumps on rotation.

      NOTE 3: If you are installing the RD yourself, make sure you adjust the B-Tension bolt correctly. Too far can cause chain-skipping on torque. Too tight will cause the upper jockey wheel to foul and hinder gear changes into to larger rings. Follow Shimano’s advice carefully and you should have a silky smooth hill-conquering drivetrain.

      Hope this helps.

      1. I respectfully disagree with the comment on chainring and crank compatibility. I have run a number of combinations of 10 speed chainrings and cranks with 11 speed systems, and simply put, I would defy anyone to tell the difference in shifting quality. They are all fine. In fact, I tried to measure the physical differences between 10 and 11 speed rings and cranks. The thicknesses at the teeth are exactly the same (as one would expect given the inner dimensions of 10 and 11 speed chains are identical). Since the tooth pitch is exactly the same as well, exactly what do you mean by “chain gates” and “pickup dynamics”? My recommendation is to save your money and use your existing crankset. As for gear ratio, given that you are already running the compact, there is no difference at the top end to give you the “spinning out” problem. Go for it!

        1. Respectfully,
          This is a user problem.

          As many have, I have run both drivetrains for many years. However, to ‘save your money’ simply refrain from upgrading.

          Of course, there are always components that can be ‘mixed’ against the manufacturer’s advice, but there are issues.

          FACT 1: FSA’s Technical Manager [Jeff Donaldson] comments;
          We…don’t consider the N10 to be forward compatible to 11-speed

          FACT 2: SRAM/Quarq’s Dan Lee comments:
          Ten- and 11-speed should not be mixed. Our 22 groups actually have the chainrings slightly farther apart than our 10-speed groups… the chain and front derailleur are specifically designed to work with that gap. Running a 10-speed chain on 11-speed rings or an 11-speed chain on 10-speed rings could cause chain jams or derailments.

          For the meaning of chain-gates and pick dynamics see Shimano’s technical documentation online or email their technical team.

          As for ‘spinning out,’ a smaller ring on the front [compact] will spin out long before a larger ring crank needs no remark, surely.

          Harris, Shimano, FSA, SRAM do not advise mixing 10 and 11-speed drivetrain components. This advice is good and for good reason. But you can ignore it.

          1. Your quotes are not exactly relevant since we are talking about shimano rings here. And my experience is based on real life use, as well as many others on other forums where this question frequently comes up. The manufacturers have a commercial reason for pushing you into purchases. Shimano in particular has a long history of stating components wont work together, when in fact they do. Please provide the link to the shimano technical documentation concerning chain-gates and pick dynamics, you are referring to. In any case, it doesn’t hurt the OP to defer the crank purchase and try it out before committing to the crank upgrade.

          2. I have two 6870 Di2 11spd bikes that I have upgraded from 10 speed and still use 10 speed cranks/chainrings. First bike runs a Quarq with Praxis chainrings (huge shifting improvement over standard SRAM chainrings) and second bike runs 6700 Ultegra cranks/chainrings with no shifting issues. I have ridden other 11 spd Di2 bikes with full 11 spd groupset and cannot tell any difference in the shifting.

            Shimano/SRAM/FSA are just trying to extract more money from consumers saying they *have* to upgrade

          3. I’m with Bob on this, a 10s crankset will work perfectually with a 11s setup, the inner and outer ring spacing is a non issue ramping is identical, however compact drivetrains just do not shift as well as standard (53×39) imho. The only reason to dump the CS6700 for a 11s crankset is because you can go from a standard to mid, or compact without changing crank arms.

  25. Thank you all for the great response to my question. I was trying to avoid upgrading the crankset, as I do have a 4iiii Precision powermeter installed on the non-drive-side crank arm. I guess I could move the old crank arm over to a new crankset, but was trying to avoid that. The other option I have been looking at is having the Ki2 derailleur mod done to install the longer cage on the existing 6770 Di2 derailleur, which allows you to run up to an 11-36 cassette.

    When I priced it out, it’s about a $10 difference between modding my 6770 or installing the 6870 without a new crankset, so figure I might as well upgrade and then either sell the 6770 kit or see if I can transfer it to my cross bike at a later date…

    1. I changed from 10 to 11 speed a couple of months ago, swapptd everything except 50/34 6700 crankset and have had absolutely no problems. Front shifting is slightly quicker due to firmware upgrade alone, rear shifting is silky smooth.

  26. I’m aware of the firmware upgrades that eliminate compatibility between 10 and 11 speed electronic components but does anyone know if you can go backwards- Using a FD 6870 with an otherwise 6770 system?

    1. Short answer is, if its a newish FD6870 with version 2.6 firmware or above then no, if it has 2.6 then you can “backdate” it if you have the Shimano interface. If it is version 3 firmware then no again AND you can’t backdate the firmware either.

      1. Thanks Andrew- that was pretty much what I figured. I’ll have to hunt down a 6770 der then. The 6870 is less expensive so I was hoping to just buy it instead.

        1. I went down that road with the RD6770 to 6870, ended up buying everything but the crankset and some wires, good news was yep you’ve guessed it, 6700 kit goes for a premium on ebay these days, got more for FD and RD than new 6870 kit, overall just about covered my outlay – after ebay fees – so might pay to upgrade all especially if you need new chain and cassette like I did.

  27. 6870-FD Microadjustment – has anyone got this to work. This is explained on page 57 in the Dealer manual. When attempting this – the FD simply does not respond to the switches. I have a system that was upgrades from 10 speed 6770 to 11 speed by replacing both front and rear derailleurs with the 6870 versions. I have seen on other forums that several others seem to have this problem – but can’t find a solution posted anywhere. Would this be something that needs a firmware update to work? I have not upgraded the firmware after replacing the 6770 derailleurs with 6870s. Shifting works fine but I am getting some chainrub at the front in the 1st/2nd cog and big ring combo. FD limits are correct and alignment is ok.

    1. Yes you will need to update the system to get this function to work. However I have found this function of little use and only affects the range during the shift, but does not seem to effect the mechanical adjustment much if at all. Also some/most bikes due to chain line you will always have rub in the two extreme combinations. To make matters worse if you are using front rings with 10 speed spacing it will exacerbate this condition.

  28. Are there different cable lengths available from the shifters to junction A? Had an recently upgrade to Ultegra Di2 completed and the extra cable hanging below the handle bar is very irritating.

    1. I’m assuming you’re using 6870 Ultegra with the seperate cables to the front junction box, if so then yes the cables are available in lengths from 300 mm up to about 1500mm with suitable steps in between, in the UK either Wiggle or Chain Reaction do them for about £12 – 15 online each, I used 400mm on mine at the front and they turned out just about right, obviously depends on the width and design of your bars and stem.

    2. With reference to Andrew’s reply below, if you don’t already have one, you’ll need the di2 wiring tool (TL-EW02) they’re about £3 in the UK.

  29. Hey there,
    I think it was discussed sometimes ago but I couldn’t find it in older comments. Sorry for asking again. My current setup is 6870 front/rear derailleurs, 6770 shifters with SM-EW67-A-E junction box and SM-BMR1 short external battery under BB. My new frame Argon 18 Gallium pro. As far as I see it doen’t has holes for external battery mount. (under BB or chainstay). An option is to buy a SM-BMR1 with long battery mount and have it installed with downtube bottle cage holes. Or I can try to revise my setup with internal SM-BTR2. In this scenario which part do I need to chage? a new battery and junction box and etc..

    many thanks for your replies and apologies if I double same topics.

    1. To use a BTR2 you meet to change the EW67-EW90, buy cables to the shifters to EW90, buy cable to junction B to battery, buy a battery and charger. Or buy a internal battery kit from me and you can use everything you have without changing any thing. My kit includes an in-line charger and is plug and play. See my ebay listing, my user name in “eapathome” you can buy it direct from me or on ebay. Just be aware I’m in Europe now and will be home from 3/29-4-1, and than back here, so let me know if you want one.

      1. But it says “Since the February 2015 firmware update, the older SM-EW67-A-E Front Junction A is no longer compatible with the BTR2 Internal Battery.”
        How am I going to use it with your kit without changing my current EW67?

        1. That’s if you use the Shimano battery, if you use mine it will work with your setup the way it is, with the EW67.

          1. Okay, thanks in advance. I let you know when I got my new frame.

  30. Hi good people of this forum,

    Has anyone had this problem before, just started yesterday. I have the DI2 11 sp, it came pre fitted on the bike, never had a problem. Now if I put it in the small chainring, I am unable to change gear at the rear, but if I put it in the big chainring, it works fine can change gears at the rear. The battery is showing fully charged. I have the SM-PCE1 (pc linkage device) so will run a check. But just wanted to know if they was something specific I should do (ie a certain update)

    Many thanks for your help

    1. Greetings, Barry:
      I have the same set up as you, on a Specialized ROUBAIX purchased new, November 2015. Have not, in this relatively short time, experienced issues you mention. Sometimes, when I felt shifts not to be very smooth I doubly verified DI2 specs for mechanical adjustment/clearances. Have never hooked up to software, assuming dealer had attended to the necessary.

      It is evident DI2 wire-connections are delicate, requiring a special tool for connect/disconnect. Irrespective, contacts are susceptible to wear. So, I tinker not with electronic hardware. One, significant observation: too frequent shifts do affect smooth transitions on MY bike. Only guessing, that is due to build-up of electrical resistance caused by temperature change within the circuitry.

      My suggestion: Put your bike on a service stand. Start off cold. Wiggle the connections while shifting. Good luck!

    2. Never had this happen to me but for what its worth, I would personally rule out any suggestion of the fault being down to dicky connections to the rear derailleur as it works fine on the big chainring and there is only1 cable feeding it. I would lean more towards it being a fault that lies within the main electronic control circuit in the battery mount, especially if it is external and subject to damage/water/dirt attack by the elements. As you say, the next obvious check is through your PCE-1 which may identify the problem. Not much help I know, but good luck.

  31. So much awesome information on this site. I was hoping you may be able to help me with this problem.

    I have a new TT bike with Dura Ace 9070 as standard. The bar end shifters that came with the bike are the single button variety that only changes the rear gears. I was wondering (before I shell out more money on the double end shifters) if there is a way to reprogram the single shifters so that they could change the FD? E.g. hold both buttons down to change FD.


  32. can i take off my 11 speed dura ace di2 (current model) and simply replace it with a medium cage ultegra Di2 if i wan to fit an 32 ultegra cluster? off to the Alps and need a granny gear. Tried fiddling the B screw and reversing it but just not enough clearance

      1. Your Dura Ace needs to be of the new type or else you cable won’t fit.

  33. On the side of the SM-EW90-A 3-port Junction Box there are 2 terminals which are covered by a square rubber flap. Can these be used to connect the SM-PCE1 interface?

    1. No it’s for the charger for the BTR2, PCE1 has a round plug and can plug into a shifter port or to a component.

      1. Can I charge my internal battery using the pcme1 or can I only use the special charger for internal battery

        1. No you cannot charge the battery with a PCE1, you need a BCR2

  34. Hi Carlton, lots of interesting stuff here but sadly nothing to help a very new DA Di2 user. My upgrade kit (new just before Xmas) comes with multi shift of the RD which I don’t like. My reading is that the default setting should not do this and of course I updated the firmware when I installed the kit. Was this a revision to the single shift? If so how do I return it to single cog shifting? Incidentally I use a Rotor crankset with Q rings: the FD works perfectly. Regards, David

    1. Within the software tool that updates the firmware there are settings to change the shift settings, it’s in the customization menu.

      1. Thanks for the very prompt reply: is that with SM-PCE1 or SM-BCR2.

        1. Author

          The Shimano e-tube Windows-based software is compatible with both the SM-PCE1 and SM-BCR2. It’s a free download http://e-tubeproject.shimano.com/

          You can either disable auto-shift all together, or you can increase the delay between each auto-shift. You may find that you prefer to leave auto-shift on after increasing the delay time between shifts.

        2. Done that, seems to have worked and was easy. I’ve ridden Sram for years and now I have shifting that works close to that. Many thanks, David

  35. Hi, Last year I upgraded my Ultegra Di2 10 speed to 11 speed. I used the externel battery. After a while I got problems with shifting both my front and rear deraillers. I checked everything and posted my problem here. At the end I changed my external battery for an internal battery and did a reset of my rear derailler. Now I have the same problem again. A few weeks ago I went to my local bike store to solve a little problem with my rear wheel. When I left the store and went back home after a few miles my Di2 system stopped working. The battery was not empty.
    At home I tested the system with the interface for the internal battery and the pc reported no problems. After that I have made a few rides that went well. Now I have the same problems again. Neither my front or my rear derailler will shift.
    I changed the 5 port junctionbox for a new one and the problem was not solved.
    I don’t know what I can do else to solve the problem. Does anyone have a good tip for me.

    1. I forgot to menton that I also changed al cables and the internal junctionbox.

  36. Can someone tell me what ST / SW stands for?

    1. Someone please correct me if I’m wrong but if you are referring to the prefixes for Shimano part numbers, I don’t think they relate to any specific words as such, other than a loose link maybe, for ST to STI (Shimano Total Integration) for all levers and SW for all Di2 SWitches. Purely guesswork guys.

  37. I am new to this forum and have recently finished finished building and setting up a Shimano system based on a Colnago frame. I have used Di2 RD 9070 and FD 9070 front and rear derailleur actuators on a CS-9000 11 speed cassette and FC-9000 172.5 MM 39/53 Crankset. All-in-all very happy with the final result after initial setting up. Changes up and down are fast and silent at each end and the system runs with very low noise, with the related benefits to performance. So very happy overall apart from one odd glitch: the downshifts from the top cog (11) will simply not move to 10 following one change command. It always requires a second shift command to go to 9. But will then happily shift back up to 10. Has anyone else come across this issue? Maybe it is my relative lack of experience at setting up? Mechanically I believe the H and L stops are set correctly but maybe some fine tuning required? Or maybe its firmware? Should I upgrade the firmware as a first step, or can anyone offer another idea/check/solution first? Thanks for any help and advice.

    1. Hi Graham,
      As you can see from the many comments here making sure your firmware is current is always a good 1st step when isolating problems.
      Have a go at that solution before changing tack.

      We love Di2!

    2. Author

      I’ve experienced this problem. Your electronically adjustable alignment is most likely a “few clicks” too wide.

      1. Thanks to James and Carlton. I am in the process of acquiring the right equipment for the firmware update so will sort that later. Sadly that bike is in SW China and I am in NW China just now so will not be able to recheck the electronic alignment until I get back there. One of the challenges of living and working here. I assume by that alignment you mean the trim setting on the 5th cog as described in the article? Maybe its not quite in the optimum position? Also I had to acquire the parts from different sources too, so there is no guarantee that the firmware levels match completely out-of-the-box. Anyway I will recheck and report back here for completeness. Thanks again.

        1. Author

          Yes, the fifth cog trim position is what I was referencing. That should fix your problem. Good luck!

        2. @Graham Bannerman
          Based on recent experience purchasing heavily discounted ‘world renowned’ name-brands in Shanghai and in Hong Kong, I’d be leery x 2 buying stuff in China :). In my case, packaging and specs were right on but performance way off. just saying and you’d probably agree.

  38. carlton.great reference site. ???? IS THERE ANY SIMPLE WAY TO UPDATE Di2 FIRMWARE ON A MAC (OS X)??????
    appreciate any advice. cheers. Tony

    1. Actually the it is incorrect to suggest E-tube cannot run on Mac .
      All my customers Di2 systems are addressed on a Mac.
      To run E-Tube software on a Mac you must run Windows on your Mac. The most trouble-free way to do this is to have a dedicated hard disk with Windows installed on it. This is my standard practice.
      The other, more problematical way, is to partition your hard disk and add a Windows partition and run the E-TUbe software on that partition.
      In short, YES you can run E-Tube on your Mac. No, you cannot run it on OSX. YES you can run it on your Mac but you must be running Windoze [preferrably Windoze 10]. Spelling for humour!

  39. HI Carlton, great page.
    Do I understand that as long as I don’t update my 6770 Di2 with new firmware I can use a 6870 rear mech with my 10 speed set up?

    1. You’ll probably find like I did that the 6870 rear mech has V3.5 or thereabouts firmware and won’t work with the rest of the 6770 kit which is on pre V2.6 firmware. I had to replace front mech, front SW67 with SW90, new wires to shifters and new internal battery. If you can get a second hand rear mech (6870) with old firmware you might be able to do it, you can’t backdate V2.6 or later firmware to earlier either.

      1. Good news is that 6770 kit goes for really good prices on ebay 🙂

  40. Hi, my wife hs the Ultegra 11spd and it has been working fine. Did a very wet triathlon yesterday but was shifting fine throughout the bike section and then picking the bike up the front mech has shifted into its lowest position and refuses to shift, battery is fully charged but still won’t shift. Its all internal and removing the seat post etc doesn’t show any water. Any ideas?

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