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Cervelo S5 Red eTap AXS

Road Bike Testing in the Peak District

With aero road bikes getting lighter and climbing bikes getting more aerodynamic, you could be forgiven for wondering whether there was still a tangible real-world difference between the two genres, particularly for mere mortals. As my regular ride is a 2018 Cervelo R5 with 11-speed SRAM eTap and rim brakes, I was extremely interested to see just how different the latest aero S5 with new 12-speed SRAM RED eTap AXS and disc brakes would feel around the hills of the Peak District.

Cervelo S5 sram red etap axs


I admit that I was not initially too impressed with the aesthetics of the latest Cervelo S5 when it was first launched, with the radical upwardly angled V-shaped stem looking very awkward to my eyes. However, the S5 looks much better and more cohesive in the flesh; the stark side-on view depicted in lots of publicity shots is its worst angle, and as a three-dimensional object it drew a number of admiring comments from fellow riders who hadn’t seen one before.



There is certainly no doubting the purposefulness of its looks, especially from the front, where the frame, handlebar and seatpost all look impossibly slender and very clean with no exposed cables at all.


Cervelo S5 sram red etap axs

First Ride

Very excited to experience this cutting edge machine, I jumped on board and went out for a quick spin as soon as it was delivered. Almost immediately I jumped back off again to check that the tyres hadn’t been inadvertently pumped up to 160psi, such was the rear end stiffness; Safe in the knowledge I had 70psi in the tyres I set off to the hills.

Thirty breezy kilometres later I was pretty impressed with its speed and very impressed with its sure-footed handling on some fast, and occasionally bumpy, descents. It felt fantastically planted, carving down through open bends at speed despite the blustery wind. The long, steady five kilometre climb went well too, with a time pretty close to my best, despite the weather and a bike I was not too familiar with. 


Cervelo S5 sram red etap axs

The Cervelo S5 at Speed

For once I actually looked forward to the chaingang part of my regular Tuesday night ride, hoping that rather than simply hanging on and waiting for the hill home the S5 would miraculously transform me into a powerful rouleur. After feeling great again on the early hills, despite its weight penalty over my R5, the S5 made perfect sense, cutting through the air on the 50kph flat section, feeling fast and smooth.


The back end no longer felt stiff at this pace, it just felt taut and perfect for eating up the miles at high speed, with me sitting perched forwards on the tip of the stubby Prologo Dimension TiRox Saddle


Cervelo S5 sram red etap axs

SRAM 12-Speed AXS eTap Groupset

After all the hype I was really keen to try SRAM’s new 12-speed AXS eTap Groupset, having spent two years loving their 11-speed eTap predecessor. Right from the off there were no histrionics, no fireworks or fanfare accompanying each wireless shift; the next required ratio was simply selected quickly and quietly, whether under pressure or not, I was impressed.

Cervelo S5 sram red etap axs

SRAM RED eTap AXS Gearing

The lever shift action on the 12-speed eTap is slightly softer than with 11-speed, and the actuation perhaps a little more muted, in keeping with the quiet drivetrain. SRAM hasn’t managed to hide the bulk of the hydraulics as well as Shimano has with their Di2 shifters either, and the hoods sit almost two centimetres higher and one centimetre wider than my 11-speed eTap rim brake ones - not good or bad, just different. This is certainly worth bearing in mind if you have small hands though. 

Whilst my legs certainly weren’t aware that I was pedalling an innovative 35/48 chainset or that I was now in possession of X-Range gearing, I did notice how quiet it all was, both in terms of shifting and while pedalling. SRAM’s idea behind the new chainset and cassette ratios is to improve front shifting by only having a 13-tooth gap between chainrings, and then to make up the range with a 12-speed cassette that features a 10-tooth sprocket at the bottom. This configuration does require a new standard of freehub, the XDR driver, to accommodate such a small sprocket, but it has the advantage of providing more single tooth jumps than on a standard cassette, so finding the right cadence is easier.

Cervelo S5 sram red etap axs

The fluid-damped Orbit chain management system worked superbly, it controlled the chain very well without the use of a clutch mechanism; even deliberately harsh bunnyhops failed to elicit any chainslap noise from the back end. This single rear derailleur will cope with gravel and cyclocross duties as well as it does with road rides.

cervelo S5 sram red etap axs brakes

Hydraulic Disc Brakes

With a three day weekend full of riding ahead I listened to my backside and substituted the somewhat punishing Prologo Dimension saddle out for a Fizik Antares, and it immediately improved the bike’s comfort massively for me; so much so that I logged 250km in the next three days with no issues at all. One of the hilly rides also threw one of the S5’s advantages into sharp relief when we were caught in a sudden downpour and the hydraulic disc brakes came into their own, with no discernable drop in performance compared with the dry. The brakes were also totally silent during my tenure, with no squealing or catching. 


Wheel Choice

The DT Swiss ARC 1450 wheels come in at around 1,600 grams for the pair, so not super light but pretty good for a 48mm deep, 25mm wide, aero wheelset. They matched the frame well, both visually and performance wise, holding speed well and getting less affected by crosswinds than I feared with excellent stability even in blustery conditions. They were already set up tubeless, and with the extra width of the rim giving the tyres added volume they inspired plenty of confidence heading into corners, daring me to hold off the brakes as long as possible.

cervelo s5 sram red etap axs

Handlebar and Stem

I found the low-drag handlebar very comfortable, with a nice compact shape that made riding in the drops feel extremely natural. The V-shaped stem and aero bar are actually two separate items that can be mixed and matched to achieve the width and length required for the perfect position, despite looking like an integrated setup. I was also impressed with the R.A.T. (Rapid Axle Technology) on the wheels, with them proving every bit as fast and easy to use as quick releases but with much greater security and stiffness.

Cervelo S5 Sram Red eTap AXS app

SRAM Red eTap AXS app

SRAM’s AXS smartphone app was easy to pair up and use, with the individual battery status information useful and wireless firmware update simple to do. I experimented with the two alternative shifting modes accessed via the app too; Sequential performs front shifts automatically to maintain cadence and Compensating makes rear shifts to compensate when a front change is made. I didn’t spend too much time trying to get used to these aids, but for me they felt a little superfluous - I sometimes change gear precisely because I want a change in cadence, so having the bike work to keep me at a certain RPM wasn’t always what I wanted.

Perhaps with more miles I could have got used to it, but I think that the nice thing about the AXS app is that it absolutely isn’t necessary for the business of enjoying the bike, but if you want to get involved then it's a great extra dimension to have.


cervelo s5 sram red etap axs

Final Thoughts

Rather unsurprisingly, my conclusion, after 500km with the Cervelo S5 AXS eTap, is that it is an amazing machine, and one which need not be reserved for use on pan-flat courses by pro-racers either. It proved itself a worthy companion on long, hilly Peak District rides, giving very little away to ostensibly more climbing orientated bikes uphill, and then really flew when the road turned downwards.


cervelo S5 sram red etap axs

There is still an obvious difference in feel between the sprightly Cervelo R5 and the powerful S5, but neither feels out of place in the other’s territory at all, and the science suggests that most of us would gain some benefit from an aerodynamic bike like the S5 even on hillier rides. The SRAM AXS eTap 12-speed is a very worthy successor to its groundbreaking 11-speed forebearer, with the innovative gears giving a wider spread of useable ratio options and allowing an optimal cadence to be found more frequently than with a traditional 11-speed set up.

The Orbit chain management worked extremely well, controlling the chain and keeping the whole system noticeably quiet. Whilst some riders will love tinkering with the app and others will ignore it completely, everyone will appreciate the quiet smoothness of the Orbit chain management system.



Shop the Cervelo S5 bike range


About the Author

  • About Tim: Tim loves anywhere with long, hot climbs and rides in Europe as often as possible. He lives on the edge of the Peak District, so has to make do with short, cold climbs instead for most of the year.
  • Article Published On: 08 October 2019

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