SRAM Force AXS vs Shimano Ultegra Di2

I ride both, Shimano is far superior in every way - shift quality, shift speed, shifting under load, battery life, hood shape, you name it.


I’m almost certain that 12spd shimano uses the same mounting points as 11spd so dzero should work for 12spd also. It may not match up aesthetically as well though.


I work in a bike shop, and while I haven’t ridden the Canyons, I’ve ridden a lot of groupsets in the last few weeks…

In terms of non-biased facts, the Shimano is more efficient than the SRAM, mostly due to the SRAM flat top chain and the 10t cog. So, if you’re concerned with gaining every small advantage, that may be good to consider. However, the Shimano powermeter is a joke, and everyone knows it. I would not trust anything that thing spits out, it’s accurate about as often as a broken wristwatch.

In my personal opinion, I’d go with Shimano and get a third party PM if you have the cash. The Shimano shifts faster and “better” (again, personal opinion), and I just enjoy the “feel” more. I’ve had both SRAM RED and Shimano Dura Ace on my bikes, and I’ll always choose Shimano from now on.

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OP said the Shimano build had a 4iii power meter. There are no major issues with those. If you have a Garmin bike computer, Shimano Di2 allows you to control the screens from buttons on the hoods. As others have mentioned, testing has shown Shimano chains to be more efficient probably saving you more time than the weight savings.

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Correct. Courtesy of powermetercity:

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Overall, I think my post in this thread is still up to date and covers pretty much all points.


  • Both are great groupsets.
  • Do not waste money on a Shimano power meter.(*)
  • Ergonomics (hood shape, buttons, etc.) >> features. Subjectively SRAM wins by a kilometer, even though I came from Shimano mechanical, I kept on mis shifting even after two weeks on a Di2 loaner. 0 mis shifts with SRAM. And I vastly prefer the hood shape.
  • SRAM has more and more flexible gearing options.
  • The 10-tooth cog (lower efficiency, blablabla) does not matter in practice, especially for us amateurs. It is fine.
  • Other features such as shift speeds or “shift quality” do not matter in practice.

(*) Even if you go for a Shimano groupset, get a Quarq Red-level crank, a Quarq power meter that mounts Shimano chainrings and use that. Rotor cranks are a great alternative. Or use Assioma pedals.

Edit: @Power13 has me beat, yes, get the red bike. Red bikes are the second fastest, they are only beaten by yellow bikes. :grin:

I don’t think that’s universally correct, pricing depends on where you live. I live in Shimano land (aka Japan), so we actually pay more for Shimano gear than if I were to order it off of bike24 or so. One factor to consider is that SRAM gear is less common, so you might not be able to walk into a LBS and pick up a pair of brake pads for your brakes. But if you order online, pricing and availability are comparable in many markets.


sure but a Red crank with power meter gives you no options on the crank. And then there is this:

In a perfect world I’d have stuck with Shimano, it does feel like it shifts faster and although practically it doesn’t matter, sometimes the shifts are slightly delayed and thats annoying.

I don’t think your sentence makes logical sense. (Maybe you hit reply too soon, happens to everyone.)

What do you mean? Did you mean that going for Red cranks gives you no options on chainrings? The Red, old Force and Quarq D1/D2 cranks are compatible with Quarq’s DFour power meter, which mounts Shimano chainrings. Officially, it is compatible with 11-speed chainrings, but as @mhandwerk pointed out, they seem to be compatible with 12-speed chainrings, too.

I mentioned efficiency (“the 10-tooth cog”) and shift speeds. Like I wrote, I think neither matter in practice.

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They’re both excellent groupsets. I think that red and purple looks awful, but I have 2 black bikes and a matte orange bike, so what the heck do I know anyway!?

Pros for shimano - like the shifter shape better, so much easier to bleed brakes. I like the brake feel better.
Con for shimano - I find it hard to feel the 2 different buttons when wearing thick winter gloves, so I have my di2 shifters setup sram style, with the right hand moving both FD and RD outboard, left inboard

Pros for sram - shifting is much more intuitive to me. In house power meter still regarded as one of the best
Con - brake bleeds are a pain in the ass, small chainrings are weird to me, even if it’s technically a bigger gear with the 10 tooth

I swap wheels between my road and cx bike and had the road di2 first, so I went shimano on the cx bike with same size rotors to make the swap effortless.

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Some purples work, but I agree, this one ain’t it. I really like the purple the CAAD12 special edition came in.

And orange is a great color. I’m over black, there is too much black in the world. What’s the point of getting the equivalent of a sports car and pick a subdued color? :slight_smile:

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I personally prefer SRAM hoods and shifters. I find it much more intuitive. Every time I go from my SRAM bike to my Shimano one, I screw up a few Shimano shifts. It never happens the other way around. I must have the only one, but my Shimano front derailleur drops chains. Shimano does last longer, but SRAM is easier to charge, and in an emergency you can swap the batteries. Shimano brakes are better. Shimano replacement parts are far easier to get your hands on. Not a fan of the red and purple combo.


ok, highly limited and expensive options.

Want to swap from 46/33 to 50/37 or 48/35? Pull out the credit card its going to be expensive.

And what happened to the pro options (asking for a friend)? Biggest you can buy is either the Aero 1x TT option, or 50/37.

Some things I like about the SRAM Red AXS crank, but with integrated PM it aint cheap and aint very flexible.

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The compatibility chart you posted only pertains to SRAM groupsets, not Shimano.

Quark’s D1 crank is a relabeled Red crank. The D2 is a relabeled last-gen Force crank. Both are compatible with the DZero and DFour power meters. The two only differ by their chainring mounting options. The DZero is for SRAM chainrings and the DFour for Shimano 11-speed chainrings. But they also seem to be compatible with 12-speed chainrings. So I could mount the power meter and chainring combo that @mhandwerk posted directly to my Force cranks in lieu of my DZero power meter and 1x chainring.

You don’t need to go with SRAM 2x power meter chainrings. Not sure they anre even compatible with Shimano’s 12-speed groupsets.

I run SRAM with a HG chain. All the watts!

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Either I’m missing something, or you stopped talking about the 2x Red AXS crank with integrated PM and 8-bolt interface in my original post.

This is my crank, and retail pricing for chainrings ‘swaps’

Expensive and not flexible.

Yes, you are indeed missing something. I initially posted this (added emphasis):

So we were talking about going the Shimano groupset route, but replacing the Shimano cranks for either SRAM + Quarq cranks for Rotor + powermeter cranks. You wouldn’t want to use SRAM chainrings in that case, i. e. the (very much real) issue you point to is not relevant here.

@mhandwerk added to that by pointing out that even though officially Quarq’s DFour power meter (Shimano mounting points version) is only compatible with 11-speed chainrings, 12-speed Shimano chainrings (which the OP would use) work just fine.

I have seen many people go this route: they like the accuracy and reliability of Quarq power meters, the lightness of SRAM cranks and how Shimano chainrings shift. This package combines the best of all worlds for them.

That works with flat top 12s?

I have both group sets, on two different bikes, both 12-speed. I like the Shimano better. Unlike almost everyone above, I find that Shimano shifting is more intuitive to me. I’ve ridden bikes for fun and competitively for over 50 years, and I’m afraid I’m wedded to “left hand = FD, right hand = RD”. That being said, I also find the Shimano front shifts to be noticeably faster. Both of my group sets use the Shimano or SRAM crank, respectively, and I have PMs on both; but for the Shimano, I went OEM with a Stages Left side only PM. (I have PMs on a number of my bikes, and all are “accurate” in that they vary little from the “base”… which I determined by comparing readings between each of them and using a Kicker as comparative. Are they really accurate? I have NFI; but for my purposes, all the bikes give close enough readings for training.) I’ve used Wipperman chains in the past; there is no Wipperman equivalent for the SRAM Flattop chain, so you’re stuck with SRAM’s chain. As far as efficiency, I’m not sure for most of us the marginal gain is significant.

One thing I have noticed with 12-speed (both groups) is a distinct propensity for more dropped chains. I rarely drop a chain in 11-speed or lesser-speed groups, but it occurs much more frequently with 12-speed. With the Shimano bike, I “fixed” it by adjusting the FD (done on my phone, which was very cool!), but I will admit to a slight bit of chain rub in certain extreme cross-chained gears. With the SRAM bike, I had to get a chain catcher, with which apparently early versions of Red came. Lots on the internet about this, and that SRAM is “finicky” when it comes to having the FD adjustment correct. Of course, this could be user error as well. YMMV.

FWIW, I bought the SRAM bike first because it was on sale and I got a really good deal. But with the Shimano bike, I had a choice and willfully decided to get Shimano even though it was slightly more expensive. But too be honest… the pros seem to be able to use anything with little problem.


While riding my Sram 12s yesterday I remember another flaw and I think shimano 11s shifting seemed a lot better. I have a few gears that are clunky on my Red and Rival stuff and that never happened with Shamino. I confirmed with others that they have the same issue.

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Both Sram and Shimano groups are great, though I haven’t used the new 12spd Shimano R8150 only the 11spd di2 version. I recently changed to Sram Force AXS. I have to say I like Shimano better. I prefer the ergonomics and shifting platform of the Shimano, and I feel like it shifts better. Sram is a bit easier to set up, but thats a one time thing and the potential gear ratios are slightly better with Sram. I found the Shimano battery to last longer between charges. I like the Quarq power meter it works great, as does my Rotor I Have no experience with the 4iiii system. Sram does rely on a 10 tooth cog to achieve a taller/bigger gear which does result in more chain friction due to the tight turn. I don’t have many wide open descent so its not really an issue for me.