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So far it’s a solo ride.

AC Tech Talks - EPS vs DI2 vs AXS

Derek Yarra |

Did you think we were done talking about drivetrains? Well, we're back with the final installment. A few weeks back we discussed broadly our thoughts between electronic and mechanical systems, and  last week we went in depth comparing the mechanical gruppos from the big three—Campagnolo, Shimano, and Sram. This week, we're taking the same brands but are looking specifically at their electronic counterparts. EPS, Di2, and AXS. Do we feel the same about their button-actuated-servo-motor kits as we do their mechanical siblings? Let's get into it. 

electronic shifting header

As we all know for mechanical, each brand has always carried its own traits as far as the user experience and feel is concerned. Would you say that’s carried over to their electronic groups?

Chad:  I would definitely say that is correct.  Shimano is ultra smooth and precise and very well finished, but can be a bit vague in feel and has the most complex shifting system of the three. SRAM has a fantastic, ground breaking, but very common sensical shifting pattern but still feels the cheapest of the group. Campagnolo is (in my opinion of course) the best looking and has the most definitive shifting feel, though like mechanical, Campagnolo groups the ergonomics take a bit longer to get used to and it’s a bit clunkier.

Robert:  Absolutely. Although the hierarchy of the components will vary a bit in ergonomics. Mostly thinking about Shmano's GRX. Their mech vs Di2 the control lever bodies are nothing alike in shape. In "general” though, yes I would say the flavor is consistent from mech to the electronic counterparts for Sram & Campagnolo.

Derek:  Definitely. While the electronic groups all bring on their own traits and idiosyncrasies, it’s interesting how they all still feel very much cut from the same cloth of their mechanical counterparts. Even Sram, who’s eTap functionally is far different from mechanical double tap, still very much feels Sram. I’ve always felt Campagnolo had a unique feeling in how the chain cascades from one gear to the next, and that feeling is still there in EPS. I’m not sure if that makes sense, it’s a tough thing to describe.

electronic sram campagnolo shimano front derailleurs

Last week we got a sense of your preferred mechanical groups, would you say your brand preference transitions over to their electronic offerings?

Chad:  To make it clear from the onset, I think each of these groups work very well and would have no problem having them on my bike.  I also feel that the more time you spend on any of these electronic groupsets, the more you get used to it and the better it works for you.  For example, after spending some good time on Campagnolo EPS and then jumping over to Dura-Ace, I didn’t like the Shimano group very much.  It felt alien and took me a bit of time to get used to the way it works and to where I feel comfortable.

However, I do like the Campagnolo mechanical system the most of the three and that remains true for the electronic examples, Campagnolo is still my choice to go with.  There are pros and cons to all of them and for me, the pros of the Campagnolo group outweigh the cons more than they do for the other two groups.

Robert:  Absolutely. Eat, sleep, & repeat Campagnolo. There is less “customization” with EPS vs the other two brands in terms of what the control levers can do. I’m a simple person so the EPS would suit my needs from transitioning from their mech line.

Derek: In some ways yes, in others no. To be totally honest, despite my love for mechanical Campagnolo I’m not that big of a fan of EPS. It works great, but there’s just something in the feeling of the shift actuations that I don’t like as much as the other brands, and definitely don't like as much as mechanical Campagnolo.  As Chad said, Campagnolo is a little clunkier, and to me that makes the system feel less refined. I also don't find the shift controls as intuitive.

As for Sram and Shimano, I'd say I enjoy their electronic kits just as much as their mechanical. Actually, for Shimano I like Di2 even more than mechanical.

electronic control levers

Does any one system suit your preferences for ergonomics and user interface better than the others?

Chad: Not really, I can adapt to any of them pretty quickly.  I do like the feel of the Campagnolo rim brake levers the most, with Shimano being a close second and SRAM third, but still feels good.  For me, less is more, I don’t need or even want shift buttons all over the bars, but if I did, that would leave Campagnolo out for now as they don’t allow for this.  For complete system integration, I feel that Shimano has the most options.

I really do feel it’s what you are most used to though.  I have spent way more time on Campagnolo than the other two and am very used to the lever placement, the feel of the brake levers, all of that.  So that for sure helps with this answer.

Robert: I've become accustomed to using the thumb as a way of accuating my drive chain, but that small bump toward the back of the EPS lever is less of a smooth transition vs say the GRX levers. I think the GRX control levers look hideous aesthetically, yet they feel great for someone with smaller hands - the blade curves back a bit more than the EPS & Sram levers. IMO having more options to adjust reach is great. So I guess a straight answer… IF I was blindfolded I would most likely choose Shimano GRX out of pure ergonomics, but take the blindfold off I’m going straight back to the EPS.

Derek: For me, it’s Shimano no question. The hood shape, shift button placement, brake levers... everything just feels right to me.While I think they're kind of ugly, I find the new GRX levers to be even more comfortable. Each lever has three programmable buttons, so you could theoretically perform all functions with a single hand, regardless of which lever you’re holding on to, and not need to clutter your bar with auxiliary buttons. 

Generally I like the Sram AXS levers but I have one major gripe—the shift paddles are too big and my fingers get pinched between them and the handlebar when braking from the hoods.

As mentioned before, Campagnolo is great, it just doesn't feel as "right" for me ergonomically.

shimano campagnolo sram cranks

Shimano and Campagnolo have been in the game the longest with Sram being a relative late bloomer to electronic gruppos. Despite that, would you say that all the brands are on par with each other as far as the technology and performance of their platforms?

Chad:  Well, no.  Sorry to say it but SRAM coming out with wireless has them sitting on top from a technological standpoint.  Better looking system with no cables, super easy to charge the batteries, easy to swap batteries from derailleur to derailleur if your rear mech battery dies during the ride.  Much easier to set up the bike, and way nicer for all the new super integrated bikes out there.  I feel that if either Campagnolo or Shimano had wireless come out now, they would be at the tip of the spear as the build quality of those two manufacturers is better.  Because of this, I would put SRAM as the leader right now.

From a performance standpoint, once the parts are installed and dialed, I don’t think any of them offer a performance benefit over the other.  And no, I don’t think shifter pods on the bar tops make you faster.  Stronger legs make you faster, not extra shifters.  So again, I would say performance wise they are all good.

Robert: So-so.. in terms of “leading” technology.. who can top who with the best features.. With a lot of bike brands developing and routing internal bars, stem, & head tube...I will tip my hat to the folks at Sram. Back in 2014 or so I was able to see the an early prototype eTap on Tetrick's bike with the Twenty16 team. All I could think about was how much time I was going to save on bike builds in the future.

Present day - in regards to initial set up Sram is the FASTEST route to go. When you think about traveling with your bike & consider the disassembly & reassembly, the wireless feature takes the win compared to the other two brands. Sram has absorbed quite a few companies and with that much tech behind the mothership, so I can only assume the tech will get better. In terms of getting what you’re paying for, I think each brand is on par with each other, but more so a different flavor. I am not a huge fan of Sram's one piece double chainring because some of our clients prefer one ring over the other and it’s not a simple one chainring replacement..

Derek:  Sram definitely did a great job, despite launching their group later. Obviously they went big by going straight to wireless, which is indeed pretty cool. As far as I know, Campagnolo doesn’t have any options for auxiliary shifters. While not essential, I do think that should be a big benefit of electronic shifting. It’s also a bit of a bummer that all of the electronic cables are hardwired to the Campagnolo battery. If you damage one cable, that’s timely and expensive repair to replace the whole unit. Regardless of these tech features though, I find Shimano to shift the fastest, especially between front chainrings, so to me it sets the bar in "performance."

axs bikes

Does Sram have any stand out features on AXS that set them apart, either good or bad?

Chad:  For sure.  Lots of gearing choices with one derailleur.  1X, 2X, one to one ratios if needed, easy to charge the batteries, easy to finish the ride if the rear mech battery dies, super clean, easy to instal.  Those would be my top positive points.  For the negative, I still think it could look better, but as we say all the time in all things related to aesthetics, that is totally subjective.  I don’t like how the power meter is part of the chainrings.  That is a very costly replacement item once the rings start wearing out, as we’re starting to see now.  But overall, this is a solid groupset.

Robert:  Light in weight & the easiest set up of all three major brands having secured the wireless feature early on - this feature is key to saving so much time during initial assembly, especially on TT & internally routed bikes/handlebars. The batteries are interchangeable & the control levers use the common CR2032 batteries which are easy to swap. The Sram AXS App has been more consistent with the ease of firmware updates.

Derek:  Obviously, the wireless factor is huge. It makes things so much cleaner and there’s no risk of wires rattling around inside the bike. I love that the derailleurs have external, easily replaceable batteries! It makes things a lot simpler than a battery that needs to live inside the frame. It’s also convenient that you can carry a spare battery when out on a long ride, just in case.

I would say I’m still not that impressed with the front shifting. In my experience it seems like it takes a moment for it to respond to the front shift command, and then the shift action itself moves pretty slow. I also hate that you need two hands to sift the front derailleur.

di2 bikes

How about Shimano Di2?

Chad:  Sure.  If you like to have a lot of options for shifter placement, you get that in spades with Shimano.  Not as many gearing options as SRAM AXS, but a good amount.  Lots of crank length options which I really appreciate.

Robert:  Shimano takes the win with customization options of their function buttons near the top of the hood, while also allowing you to run sprinter shifters if that’s your thing. Dear, Shimano.. We’re still waiting on a road 12s Di2 group...

Derek:  To me, it just performs the best. The shifts feel the fastest and most precise. The ergonomics work really well for me. As I mentioned before, the versatility in having multiple shift buttons on each lever. On a 1x bike, you can perform all shift actions with just one hand, and it doesn't matter which one. This is huge when recaching for a snack, grabbing a bottle, or you know... filming something for your IG stories. I would definitely appreciate it if they advanced to wireless, and I'm sure they're not far off from catching up to 12 speed. 

EPS bikes

And Campagnolo EPS?

Chad:  Looks amazing!  And, the rear derailleur actually looks great on Campagnolo’s electronic group. I have only used the rim brake version of the EPS group, but to me the ergonomics stand out as my favorite at least.  For sure it takes time to get used to the totally different shifting style, but that makes it fun.  Cons?  Yeah, that charging port is pretty bad, but as long as you know that and are careful, it’s fine.

Robert:  EPS is extremely precise - I like the word “precise” over “fragile”, but in the “cons” column I will have to admit I’ve had quite a few clients come back with the damaged EPS charger port. The prongs in the charger interface are so “precise” & no offense to our clients reading, but you must handle these elegant components w/TLC. I’ve since started to paint a small red dot on where that little notch is to help folks using this EPS group & it’s been helping a lot. #tricksofthetrade

IMO The EPS has a slightly slower shift actuation compared to the Sram & Shimano electronic drive chain with a more pronounced slow trim on the front derailleur.. but hey.. why rush these things - you’re out there smelling the roses and riding solo - during this social distancing time

Price is the only real downside.. If you crash out you will pay a pretty penny in the long run. So always - rubber side down.

Derek:  To me, Campagnolo just is what it is. Again, it works great and there really is nothing wrong with it. I eve think it looks great. That said, when riding it, there's just nothing that really screams out to me as being better than the others. It's also  not quite as versatile of a system. As of now, there's no real gravel option, no clutch rear derailleur, no 1x etc. etc.

Oh and for the love of God, Campagnolo, please design a less delicate charing cable connection. 

rear derailleurs electronic

What would you put on your next bike?

Chad:  Campagnolo Super Record mechanical. :-)  But, if it had to be electronic, it’d still be Campagnolo Super Record, mainly due to the history I’ve had with that brand and aesthetics of course.  In second place, SRAM AXS because it’s so clean.  Wouldn’t throw any of them off my frame though.

Robert: LOL ^ Chad, same—Mech SR for me. A solid second place for me would be Sram AXS for me in terms of aesthetic.

Derek:  For gravel, it's hands down Shimano. I do really like the Sram AXS mullet group, but the finger pinching while braking from the hoods is a deal breaker to me, no matter how much I like everything else. For a road bike, I'd be pretty happy with either system. Currently I have 1x Shimano GRX Di2 on my gravel bike and 2x Sram Red AXS, and I'd say I'm pretty happy with this selection! I'd be perfectly happy if a Campagnolo EPS group found its way onto my bike, but I don't think I'd seek it out. 

That wraps things up here. What's the deal for you? Do your electronic brand preferences mirror your mechanical ones? What's going on your next bike? Let us know here in the comments, to join the discussion on out Instagram post. Thanks for checking in!
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