SRAM Eagle 12 Speed: A Touring Bike Drivetrain With Only One Chainring Up Front?

While most of us ride with three front chainrings in order to achieve a wide gear range, SRAM has been doing its best to put the front derailleur to rest – at least on their mountain bike drivetrains.

It was 2012 when SRAM released their first 1×11 drivetrain to the world, using a 10-42 cassette in conjunction with a narrow-wide chainring profile to create drivetrain without a front derailleur. Amongst mountain bikers, 1×11 was labelled a ‘game changer’ and we’re slowly seeing 1x drivetrains on adventure touring bikes like the Specialized Awol CompRawland Ravn and Kona Sutra LTD.

SRAM Eagle 12 Speed Drivetrain 01
SRAM’s new 12-speed drivetrain has a 500% range.

What’s Special About 12 Speed SRAM Eagle?

The new SRAM Eagle 1×12 employs a huge 10-50t cassette, offering a range of 500% across the drivetrain.

To put that into perspective, a Rohloff hub offers 526% and a typical touring triple around 550%. If we’re talking gear inches, a typical touring bike could use a 38t front chainring with the Eagle cassette and get a 21-104″ range. That’s good enough for most climbs with panniers, but you will miss out on a few gears if you’re motoring down a hill.

What’s the Catch?

There are a few catches here. 

The first is the price of this drivetrain – it’s currently sky high. Considering that many of us cover some pretty serious ground, the 5000-10000km life expectancy of a US $360 cassette (yes, that’s three hundred and sixty dollars) is pretty hard to justify. It’s kinda fine for mountain biking where the terrain prevents you from riding far, but 5000km can equate to 2x month long tours for some people.

You will need to use a different freehub body on your wheel for the 10-50t cassette. It’s called an XD driver and it’s only available on some hubs. To complicate matters further, SRAM Eagle is also 12 speed; you won’t be finding any spares in shops for a while yet.

One other gripe could be that there are significant jumps between each gear. Sometimes you just want to modify your gear slightly for an uphill rise. The Eagle works out to be about a 16% average jump per gear, compared to 12% on a 11-34t touring cassette, or 14% for a Rohloff hub.

And finally, there is no 12-speed shifter for road handlebars. This drivetrain is limited to flat bar bikes only.

SRAM Eagle 12 Speed Drivetrain 02
SRAM Eagle XX1 12-speed Cassette. Image: PinkBike.com

Is There a Cheaper Way to Go Front Derailleur Free?

There sure is!

Shimano have recently announced an 11-46t cassette which will fit onto a standard drivetrain. It offers 418% range, so it won’t quite stretch to give you both the small and large gears, but it will get you a 21-89″ drivetrain which has you covered for hills. Or you could gear it to 27-114″ which will give you more top-end if that’s your thing.

Better yet – you don’t need a special hub driver, plus this XT-level cassette will likely be available for a QUARTER of the price of the SRAM Eagle (sub-$100). The only downside is that it will come with a significant weight penalty.

Shimano's 11-46t cassette will be much more affordable when it is available in an XT spec.
Shimano’s 11-46t cassette will be much more affordable when it is available in an XT spec.

Is SRAM Eagle A Good Touring Drivetrain?

Not right now.

SRAM Eagle is cost-prohibitive, it requires a specific freehub body and has rather large gaps between gears. That said, this kind of tech will filter down to lower level components which will make it more affordable in the years to come. SRAM’s NX level 11-42t cassette is available from just US $79 right now (full 1×11 drivetrain is US $310), if that’s any indication.

SRAM Eagle 12 Speed Drivetrain 03
SRAM Eagle XX1 12-speed Cassette. Image: PinkBike.com

SRAM Eagle Prices and Weights

Total group:$1,417; 1456 grams (not including BB)
Crankset: $425; 465 grams (with 32T chainring)
Chainrings: $99
Chain: $60-85; 250 grams
X-1299 Eagle Cassette: $420; 355 grams
Rear Derailleur: $289; 264 grams
Trigger Shifter: $162; 122 grams
Grip Shift: $148; 140 grams (including clamps, cables, and Jaws lock-on grip)

Total group: $1,193; 1502 grams (not including BB)
Crankset: $390; 465 grams (with 32T chainring)
Chainrings: $99
Chain: $60-85; 250 grams
XG-1295 Eagle Cassette: $360; 355 grams
Rear Derailleur: $220; 276 grams
Trigger Shifter: $127; 126 grams
Grip Shift: $118; 143 grams (including clamps, cables, and Jaws lock-on grip)

  1. When I got my first geared bike, an mtb, the “pros” in my cycling club said I should avoid “crossing” the chain (that is, running small chainring with small sprocket, or the other way around) to minimize wear in both transmission and chain. Being seen with a crossed chain was a sure sign of a “beginner’s mistake”.
    Now manufacturers and bike magazines are trying to sell us that running a chain in the same chainring but in a 11t sprocket and 50t the next minute is perfectly fine, even though today’s 12 speed chain are way narrower (and therefore weaker) than the 7 speed chain on my mtb. To be really fair, they don’t say it’s fine, they actually say nothing at all regarding wear and longevity of components.
    Nowadays the new bike “fad” is to have as few chainrings as possible, or even only one if possible. Nah, thanks, I’ll keep my triple and have my bike as versatile as it is at a fraction of the cost of these “improvements”.

  2. Hi Joe

    Contrary to popular belief, narrower chains tend not to be weaker. There’s plenty of people on 10-11s chains getting the same wear as 6/7/8s. A few blogs have done their own testing and have found the same. Of course, 12s could well be a tipping point – we don’t know yet, and it’s probably unfair to speculate.

    With regards to the crossing chains, I’d suggest the ‘average rider’ will get a better chainline through a 1x setup due to the chainline being optimised around the most common gears. Yes, in theory, you can get a better chainline with 3x. That’s assuming you’re using the first three cassette gears with your smallest front chainring, the middle five with your middle ring, and the lower three with your big ring. But in my experience, that’s not how the ‘average rider’ uses their gears! Most people will pick a front chainring and go from top to bottom of their cassette. Heck, I even find myself doing that sometimes when I’m distracted by something else (conversation, scenery, traffic, thoughts etc).


  3. Hi,
    I was not talking about popular belief but rather own experience. I have a modern mtb with 10 speed, a tourer with 9 speed, and two vintage mtbs with 7 speed. The difference in longevity in the 7 speed chains is outstanding. So much, that since my tourer has bar-ends with friction option, I’m considering to switch to 8 which uses the same thicker chain as 7.
    Shimano took quite a while to move their mtb range to 9speed, and even longer to 10speed, even though their road range already had the technology and the testing done. And those companies don’t like to waste a sale opportunity so easily… It was just too fragile for rough use.

  4. Hi im a newbie her i got trek x caliber 8 and im planning to do some upgrades for my hardtail bike. Wich is shimano xtr m9000 and m9020 gears set. Will my xtr m9000 works with shimano xtr m985 crankset double? What size would i exactly buy and what numbers of teeth?

  5. And also can i able to use the luxury 12speed black of sram will it be able to work with my shimano xtr m9000 gears?

  6. The M985 crankset should work fine with the M9000 gearing. The teeth that you require almost entirely depends on the type of terrain you normally ride. I generally recommend having gears for all occasions, so that’s a nice wide cassette and a large difference between the two front chainring sizes.

  7. I have a 1984 vintage steel road bike with a 28.6 mm OD seat tube and a braze-on for front derailleur with the cable routed from below the rear derailleur. I want to convert the bike to a gravel/commute bike. I want to run a 9-sp cassette (12-27) and a 44-32-22T triple. The shifters will be bar end (front friction, rear indexed). I have a 9-sp Ultegra (or 105) front derailleur that I could use, but those were designed for a 52T ring. Is there a mountain bike front derailleur that fits those small rings better and could clamp on my seat tube underneath the braze-on? Any other solutions? Thanks.

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