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I'm in the process of upgrading my road bike's groupset, since it's quite old now. I don't want to blow my budget so I wish to upgrade as little as I can with the most impact. I currently ride my road Ultegra R6700 10 speed groupset.

So my focus was changing the shifters and rear mec, but keeping brakes, cranks and front derailleur. I was thinking of getting everything from 105 R7000 series, but I'm not sure if it will work. Shimano manual states, that 10 speed and 11 speed groupsets are compatible between each other, on the other hand is there huge change between front derailleur for 10 and 11 speed?

I saw some questions when people wanted to upgrade from 9 speed Sora to 11 speed 105 and most people recommended the whole upgrade.

And if the upgrade is not possible, probably the breaks I can keep, but cranks would needed to be changed and probably bottom bracket as well?

Thank you for you answers.

2 Answers 2

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There's no permutation of this where you only change the shifters and rear derailleur.

The cassette has to go no matter what, because you have 10-speed and R7000 is 11. Unless you have an 11-speed road compatible freehub body, which wouldn't have been what came with the bike other than if it's a Mavic or one of the small handful of pre-11 road hubs where conversion to the longer 11-speed freehub body is possible, then you're either choosing a new cassette with a big cog greater than 32t, or you're getting a new rear wheel. (The third option is doing one of the various tricks for taking material away from your current 8/9/10 freehub body to cheat an 11-speed cassette on to it, which is an advanced topic and has risks).

The front derailleur is going no matter what. There is no compatibility what you have and 11-speed STI.

The cranks can stay; the difference in chainring spacing is tiny and not enough to prevent good FD setup.

The brake calipers can stay.

Re-examine whatever Shimano manual section you're recalling says the 10 and 11 groups are compatible with each other. There is likely some additional context.

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  • Sorry I forgot to mention, I already have 11 speed cassette and I know my wheelset can fit 11 speed on it. I would probably still upgrade my old 11 speed cassette to 11-32. Also I'm not saying 10 and 11 groups are compatible between each other, no where in the manual I could find anything about that, it's only that I wish to do an upgrade on my bike and wanted to know what are the minimal requirements for it to work. I wasn't aware that front derailleur needed to be changed as well. Thanks for the heads up. Basically only breaks are good to stay, for optimal preformance?
    – korxz
    Commented May 30, 2023 at 6:27
  • @korxz The brakes and cranks, basically. Shimano would tell you that the cranks would need to go too, but the situation there is basically that since that 11 speed chains are only about 0.2mm narrower than 10, so 0.1mm per side, the differences in how well the 11 speed chains perform on 10-speed cranks and vice versa is basically noise. Commented May 30, 2023 at 8:07
  • Understood, I already have 11 speed chain currently on. Do you think 10 speed crank will shorten the life span of my chain? As far as I know chains should lest around 5-6k km, mine is already out after 2-3k km.
    – korxz
    Commented May 30, 2023 at 8:18
  • Lifespan shouldn't be affected by the speed mismatch. It will be affected by the wear condition of the old rings, but that's always true. Commented May 30, 2023 at 15:47
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According to Shimano's compatibility chart, the R6700 groupset is only compatible with 105 R5700 and Tiagra 4600. In other words, you already have the best groupset for this "system". To upgrade, replacing the whole groupset would then be required - except the brakes. R7000 is 11 speed, and not compatible.

That being said, if you'd like a "significant" upgrade, it may be better to replace the whole groupset, as modern components require some "breaking changes". R7000 is 2x11 only, and requires wider range cassettes than what you can have with an R6700.

Especially in this range, the best you can do is to keep your current groupset and maintain it. I don't think that you'll gain a lot to replacing it by a Sora or Tiagra.

The compatibility between 10 and 11 speed is "complicated". To my knowledge, it's only Tiagra 4700 (10-speed) that uses the same pull rations as 11-speed, and some MTB derailleurs that are 10/11 speed. There's also the case of CUES, that offers 9 to 11 speeds, based on a 11 speed chain. But that's not for drop handle bars.

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  • I mean replacing whole groupset is almost as expensive as buying a new bike. That's why I was thinking of replacing just a few components. Looking at the current prices, shifters + rear derailleur would set me back 260 eurs, with front derailleur being another 30 eurs. Which is still much cheaper then buying whole groupset for 600 eurs. In original post I forgot to mention I already own a pair of wheelset and 11 speed cassette. Looking at the compatibility chart it shocked me a bit seeing cranks are also not compatible, because cranks are the most expansve thing here, I asked the question.
    – korxz
    Commented May 30, 2023 at 7:26
  • Cranks are not compatible because your current setup is a triple chainring, all 11-speed are double chainring. I don't think there's an issue of running an 11-speed chain in a 10-speed crankset (I'm running a 10-speed setup on an 9-speed crankset), but the 11-speed rear derailleurs may not have the capacity to handle a triple chainring. But if you prefer to avoid upgrading the crankset, there's even less reason to upgrade: the gains will be only marginal. What is the reason behind the upgrade? Maybe some greasing is just what your brifters need?
    – Rеnаud
    Commented May 30, 2023 at 7:56
  • (by marginal, I mean you'll only gain one intermediate speed, but it's not sure you'll find an 11-speed rear derailleur that has enough capacity a triple chainring front + a wide range 11 speed cassette)
    – Rеnаud
    Commented May 30, 2023 at 8:02
  • Sorry but I'm not quite sure why you assume my cranks have 3 chain rings. I have normal 2 chain ring Ulegra FC R6700 compact with 50-34 chain rings on it, whole Ultegra 6700 is 2x10 groupset. That's a good question why upgrade it, first there are issues with shifting, when I bought the bike 2 years ago it was advertised as 2x11 ultegra and I took it straight to the a bike shop were they have adjusted the shifting, it was after 1 year I figured it out it was actually only 2x10 groupset but with a 11 speed cassette on the hub. That's why after 2000km chain is lose and shifting is off.
    – korxz
    Commented May 30, 2023 at 8:10
  • I know just buying a 10 speed cassette would fix probably most issues, but I'm afraid everything has been damaged over the period of 10 years (this is how old is the bike) and I was thinking the best thing I could do is just change out the shifting components and breath a new life into the bike. I'm not looking in getting 20watts out of this, I just want to extend the life and improve my shifting experience, but with the least amount of money spent. This was my thinking process behind it.
    – korxz
    Commented May 30, 2023 at 8:12

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