SRAM is the second major drivetrain brand to launch 12-speed, but there is a little more to it than meets the eye


Yes! It’s finally landed, the brand new SRAM Red eTap AXS groupset. It’s of course 12-speed, but that isn’t want the American brand is focusing on, oh no, there is plenty more to this groupset than meets the eye.

>>> Road bike groupsets explained

SRAM says the modern cyclist is far different from the cyclist of old and as such has new demands for a drivetrain. The American brand has a new approach to gearing based around a 10-tooth sprocket.

Today’s cyclist is looking for a quiet, secure and smooth working drivetrain, whether that is on tarmac or gravel. A groupset should always allow the rider to be in the right gear, and allowing for personal preference is important too, says SRAM.


Tech editor Symon Lewis out testing the new SRAM Red eTap AXS groupset

SRAM Force

But before we go into the new groupset details many of you must be wondering when the hell is the Force groupset going to land? Well, SRAM did mention it but only shared that a Force eTap AXS groupset is in development.

No details, spy shots of the specification or availability timeline were shared though – but it hinted that an information update would be coming in April.

That is very exciting news, but for now it’s the brand new SRAM Red eTap AXS groupset which is available right now to buy today.

Here’s everything you need to know about the newly launched SRAM Red eTap AXS groupset.

Extra gear

At the basic level there is an extra gear, but unlike rival 12-speed groupset (Campagnolo Record), SRAM has actually done something with the extra cog at the back and brought with it a new thinking to gear ratios. This new thinking is worked around a 10-tooth sprocket at the rear which really open up a new level of options.

SRAM also said that it is fully committed to one-by and two-by and the new SRAM Red eTap AXS system covers both.

The extra gear brings a change to the cassette body, which needs to change to an XDR body. All major wheel brands will offer this to suit the new cassette from today. XDR basically is 1.85mm longer than the previous XD body to allow for that 10t sprocket without changing axel standards. You can use 11-speed cassettes with a 1.85mm spacer on those wheelsets with XDR cassette bodies.


The new SRAM Red eTap AXS groupset

SRAM Red AXS gear ratios

Now, this is where the big changes happen and SRAM calls it ‘X-Range’.

In essence, SRAM has seen an advantage in starting with a 10-sprocket at the rear – and no that isn’t just to have a massive 53×10 gear!

SRAM believes that the cyclists of today have changed and aren’t always offered what they need through current, widely available gear ratios. Those roughly speaking are:

53×39, 11-25/28, professional
52×36, 11-28, passionate/racer
50×34, 11-32, sporting/ casual rider

Instead, SRAM offers:

50×37, 10-26, professional
48×35, 10-28, passionate / racer
46×33, 10-33, sporting / casual rider

This, SRAM says, takes the range away from the front and puts it at the back for a number of good reasons.

The two advantages here are clear. You get a smaller and bigger gear at either end of the scale; a 50×10 is bigger than 53×11 and a 37×26 is smaller than a 39×25.

You also get seven one-tooth steps in the 10×26 cassette, compared to six that an 11×25 gives you with less overall range.

That goes completely against what’s been said about a bigger chainring and bigger cassette being more efficient.

Yes it does, however SRAM argues a few points here. Firstly being a smaller front chainring, which you’ll be in more of the time, means efficiency drop isn’t as much.

You also don’t need change the front mech as often because the range is at the rear. Even when you do change at the front there is only a 13-tooth jump not 16 as the standard is at the moment.

This ultimately means less time off the power and thus being more efficient in SRAM’s eyes – you’ll be lighter too.

Smaller rings equals less material in the chainrings (that has been reworked from one piece of aluminium) and less material in the cassette too. Also, as SRAM uses a standard rear mech cage (as you don’t need a long cage for the larger cassettes) which should also be lighter.


One by TT set up looks sleek

SRAM adds that you’ll only ever go in the 50×10 every now and then; either for sprints or descents and it is one hell of a big gear!

JP McCarthy, SRAM road product manager had this to say:

“Overall the biggest efficiency gain from the system is driven by having a smaller difference between the front chainrings and at the same time using a substantially larger cassette.

“So, with that and with a wider range of the cassette the rider is required to make fewer front shifts, and that is the big difference in performance in that in rolling terrain, if the rider is not required to make a front shift and stay at the right cadence then that is an enormous advantage.”

“The smaller difference between the chainrings means that its mechanically simpler, and compared to the traditional chainsets which are a 16-tooth jumps, we are about 20 per cent  better in terms of efficiency in change with only a 13-tooth jump. That also means that the recovery at the rear is only one jump too, not two or three cogs like we see on our rivals.”

SRAM Red AXS rear mech

As with the first version of the wireless SRAM Red eTap system, the latest AXS system uses the rear mech as the master for all components to join to.

It is an amazing bit of technology and can actually be used for one- and two-by which is remarkable. Remember, SRAM hasn’t had a Red one-by system before and now you have the ability to mix between the two, which is ideal.


Master rear mech is a super bit of tech

The rear mech has something called ‘Orbit technology’ and doesn’t have a clutch per se, rather a fluid dampener which is lighter weight and doesn’t place any unnecessary resistance to the spring when under slow or light movement. This in turn gives better action when shifting, according to SRAM.

The system will reduce chain bounce though, mostly for hard hitting impacts and impressively can take a massive whack, in which the system will try absorb as much of the impact before returning to position. This’ll hopefully save some mech hangers in the future!

It will never need servicing and a mineral oil is used inside; a common technology brought in from other industries that is uniquely applied here.

The new rear mech will use larger ‘X-Sync’ pulleys and ceramic bearings for increased durability and efficiency, again helping that efficiency drive. It’s also compatible with with existing eTap batteries.


New fluid dampener can take hard knocks to protect the rear mech

SRAM Red AXS new chain

You’ll have noticed the slightly different looking chain with the SRAM Red eTap AXS groupset too. This is because it doesn’t have the traditional figure-of-eight design and for good reason.

With the narrowing of the chain, SRAM wanted to get back the strength it lost and has done this by harvesting back all the strength by filling in the top half of the chain, losing that figure of eight design. This is called ‘Flattop’ for obvious reasons and is completely engineer-lead.

Narrowing the chain means isn’t only down to spacing between the cogs as SRAM says that hasn’t shrunk by much. It is more the case that SRAM, going back to a better overall experience using a groupset, wanted less friction and a quieter drivetrain to offer a more enjoyable time using its product.


Flattop chain is narrower but stronger, weighing the same as the old 11-speed chain

It really is quiet and while riding it, it was a little odd not hearing that common mechanical noise when amongst a bunch of cyclists. It weighs the same as the previous chain according to SRAM and only time will tell how long this continues for those of us who aren’t quite as good at regularly cleaning their chains.

New Chainset / Chainrings / Power meter

Another striking aspect of the new SRAM Red eTap AXS groupset is the chainset. With no chainring bolts in sight its new design is in fact one piece with the inner and outer rings being made from single piece of aluminium. The chainrings are attached to the chainset via eight internal bolts on the very inner of the crankset.

Its big claim though is that the chainrings last around 50 per cent longer than the previous version, making these a robust set of rings. Good thing as you’ll be pedalling more rotations with a smaller chainring.


New bolt design improves power meter offset readings and helps the cranks to be lighter and stiffer too

This is where the power meter is housed which hasn’t changed internally for 2019 and only changes in terms of looks. Although, with the chainring bolts effectively being eliminated you get better reliability, a stiffer crankset and a lightweight design.

SRAM launched a power meter replacement program with this setup too. Meaning if and when things get worn out, they’ll take in the old one to recycle and offer you half price replacement.

So one-by doesn’t change here, it is all about the two-by set up.

New electronics for faster shifting

The same batteries are used from the old Red eTap groupset as SRAM didn’t see enough of an upgrade with the latest battery tech. SRAM says that the batteries are still up to the job, and even with better motors and electronics give the same battery run time.

The components of the groupset are not backwards compatible though. So no using SRAM Red eTap 11-speed with the new 12-speed.

In terms of the performance of the new SRAM Red eTap AXS groupset though, more specifically gear changes, SRAM claims that it is two times faster than the previous version.

SRAM Red eTap AXS shifters

A minor mention of the previous groupset was it’s shifting speed, particularly with shifting speed being important in racing.

What needs to be considered here and how the software works is that the system has to ensure that a rider isn’t trying to activate a front change – which of course is by pressing both paddles at the same time. Annoyingly for SRAM, you would rarely press both buttons completely simultaneously, meaning a small delay is expected.

However, if you run one-by or switch the button configuration to one-button you can, in effect, get faster shifting.

New app AXS

A major part of the new groupset is personalisation and simplification. To do this SRAM links all the wireless components via the new AXS app that is downloadable on your smartphone.

This allows you to have full control of all the buttons, special enhanced functions and to log a number of bikes to the app so you can apply your settings to each bike you own, or download your settings to a bike you’re riding for a training camp or holiday for example.

However, you do not need the AXS app to use the new SRAM Red eTap AXS groupset.

The new app is more intuitive than the previous one, and with it you can change, in real time, what each button does. So if you’re a mad person and want to swap what the left and right buttons do, you can. You can have one button activate the front shift and you can customise add-ons like the blips buttons.

You can also change how many gears a continuous press of the button changes; two, three or the whole block.

The new app also has an enhanced mode, which follows in a similar vein to Shimano and its auto-change mode. This can be enabled via the app or the inside button on the the hoods.

This in basic terms changes the front chainrings either up or down depending on the gear position at the back. So move to high up the cassette and it will auto-shift the front at the same time as you go back down. Whether you use this or not will come down to personal preference, it isn’t a feature that suits everyone.

However, the compensation mode is great and can be personalised to one or two cog jumps at the rear. Shift the front up and the rear will shift up. Shift down and it’ll do the same down at the rear to make it an easier transition whilst out on undulating road. This again can be switched off on the app or at the lever.

SRAM has done something exciting here with the new SRAM Red eTap AXS groupset. It has used new tech to improve and potentially change the way we use our bikes going forward.

SRAM Red eTap ASX price list and weights

Manufacturer’s suggested retail price in GDP (incl. VAT)

2x Hydraulic Road Disc Brake w/ Power, £3,794

2x Hydraulic Road Disc Brake, £3,349

2x Rim Brake w/ Power, £3,604

2x Rim Brake, £3,159

1x Hydraulic Road Disc Brake w/ Power, £3,294

1x Hydraulic Road Disc Brake, £2,849

1x Hydraulic Road Disc Brake Aero w/Power, £3,362

1x Hydraulic Road Disc Brake Aero, £2,917

1x Rim Brake Aero w/Power, £3,004

1x Rim Brake Aero, £2,559

*Groupsets include rear derailleur, front derailleur (if applicable), controls, brake calipers, rotors (if applicable), crankset/power meter, bottom bracket, cassette, chain, battery(s), and charger.

SRAM Red eTap AXS Variants 

Power meters/Cranksets                                                                 

2X: 50/37, 48/35, 46/33
1X: 50 (Aero), 48 (Aero), 46, 44, 42, 40, 38, 36


10-26, 10-28, 10-33

Rear derailleur                                     

One rear derailleur for all chainring and cassette combinations

Front derailleur                                    

One front derailleur for all chainring and cassette combinations

Disc brake calipers                         

Flat mount and post mount for 160 or 140 rotors


140 or 160, CenterLock or six-bolt

SRAM Red eTap AXS Groupset weights (claimed)

GROUPSETS 2X With Power 2x power 1x Aero
RED Disc 2,518g +36g 2,554g 2,103g
RED Rim 2,254g +36g 2,290g 2,070g
RED Disc 2,343g +36g 2,379g 2,159g
RED Rim 2,052g +36g 2,088g 1,868g