sram eagle 1x12 xx1 and x01 mountain bike group technical details

If you really think about what you want, it’s not that you WANT a front derailleur and double chainring. You want range. And 1×11 provided that for many people, with 2x for the rest.

According to SRAM, global spec for 3x drivetrains drops 70% every year, and has done so year over year for quite some time. Now, they say even 2x spec is diminishing as 1x has become fully developed across the price spectrum. The growth was a surprise for them, actually. When they first made XX1, they thought it might be a niche product. That was 2007. Now, between road, mountain and cyclocross, they have nine different 1x groups because demand has far exceeded expectations.

But there were hold outs. Even with a 420% range on their 1×11, some riders wanted more. SRAM’s GX 2×11 boasts a ridiculous 630% range, but most 2×10 setups are in the ~515% range. But, then you’ve got the weight and complexity of a front derailleur and multiple chainrings. Surely there was a way, so they started tinkering.

The result is Eagle, a 1×12 group with 10-50 cassette spread that gets you darn close to what a double provides. But who needs that kind of range? Turns out even their top pros wanted it after trying it. Dominant riders like Nino Schurter and Jerome Clementz. Why? Not because they need more range, but because they can go faster…


Basically, Eagle is substantially lighter than a 2x, has a 500% range, and makes the bike simpler. In other words, it frees you from ever needing a front derailleur again. How serious is SRAM about this? Drivetrain product manager Chris Hilton says they’ll never tell us about another mountain bike front derailleur again. They are no longer doing any development work on mountain bike front derailleurs, and those engineers have been moved to other projects. They’re dead.

SIDEBAR: The Eagle gets its name because the bird has a massive range, is an apex predator and respected as a symbol of freedom throughout the world.

At launch, Eagle will be a premium offering at the XX1 and X01 level. Because the chainrings are direct mount, you’ll be able to build it up with lower level cranks to save a little money (and expect OEM buyers to do just that on MY17 bikes). More on that in a bit. First, it’s worth mentioning that this is a complete system. SRAM’s not a derailleur company, they’re a drivetrain company. So, in their mind, if you’re not designing a drivetrain as a system, how do you know that it’s optimized to work together as well as possible?

And optimized it is, far beyond just adding another cog. So we’re covering this in three posts – this overview that dives into each component’s technical details, a specs and actual weights story, and our first ride review. Here we go:


sram eagle 1x12 xx1 and x01 mountain bike group technical details

The most visible element of Eagle is the massive cassette. It’s about the same diameter as a 180mm brake rotor. It mounts to their existing XD Driver Body freehub and the 10-tooth cog location is the same, which was necessary to fit standard frames. That was an important consideration, they didn’t want to force anyone to buy a new wheel or frame to use this group. Compared to the 11-speed cassette, the 42-tooth cog is slightly more outboard than where it was before, which means better chainline on that then with the 11-speed groups. The 50-tooth is slightly inboard, but because of the wheel’s dish, it maintains proper clearance for both it and the derailleur.

sram eagle 1x12 xx1 and x01 mountain bike group technical details

The actual 50 tooth count came about after testing various numbers. Counterintuitively, they say it’s not always harder to make a chain move across bigger gaps, it just depends on the timing between them. Fifty became the right number in that it provided the smoothest shifts between it and the 42. Everything below it is essentially the original 11-speed XX1 cog’s 10-42, gear steps and all. They’re just a little closer together.

Shift ramps (marked in red and green) and tooth shaping on the two largest cogs help move the chain quickly and efficiently.

sram eagle 1x12 xx1 and x01 mountain bike group technical details sram eagle 1x12 xx1 and x01 mountain bike group technical details

The Eagle X-Dome cassettes are machined out of solid steel, just like the XX1 and RED Power Dome cassettes, with the largest cog being alloy to save weight.

sram eagle 1x12 xx1 and x01 mountain bike group technical details

Both the XX1 and X01 cassettes are the same except the color. Both get a PVD (Physical Vapor Deposition) Titanium Nitride coating, with XX1’s being gold and X01’s being black. The coating provides corrosion resistance and some friction reduction. The same coating is used on the chains for each group, too.


sram eagle 1x12 xx1 and x01 mountain bike group technical details

The new Eagle chainring’s design is a balance between chain wear and chain retention. The teeth are more radically shaped, with more of a shark tooth design with notches and grooves. This shape came about in part by looking at how their chainrings wore in the field. And by noticing that as riders went to a 1x system, many ended up running smaller and smaller chainrings, which meant the chain load was being spread across fewer teeth, which sped up wear.

Frank Schmidt, SRAM’s MTB drivetrain engineering manager, said with the original design, most of the load is taken by the first couple teeth as the chain engages the ring, and that causes a majority of the wear that ends up creating a sort of shark tooth shape. These new shapes help disperse that load across more teeth, which ends up reducing wear.

sram eagle 1x12 xx1 and x01 mountain bike group technical details

The tooth profile looks counterintuitive, but it’s doing several things. First, it’s preemptively putting part of the hook shaped pattern into the teeth that ends up occurring with normal wear. Then the top is notched back more to prevent that shark tooth “hook” from ever forming, which means even as the ring wears, it won’t allow chain suck.

sram eagle 1x12 xx1 and x01 mountain bike group technical details

The shape also distributes the load across more teeth – almost all the way around rather than the first two or three teeth taking the bulk of the load. The result is chainrings that have more than 4x the life of their first gen X-Sync chainrings.

sram eagle 1x12 xx1 and x01 mountain bike group technical details

Just as important as chain retention is letting it go when the time is right. We spun the cranks fast and slow and the chain glides off the bottom of the ring effortlessly…it’s very smooth. And it should stay that way no matter the conditions; all of those little nicks, grooves and angles are there to shed mud and grime.

sram eagle 1x12 xx1 and x01 mountain bike group technical details

All Eagle chainrings are direct mount only, and at launch they’ll offer 30/32/34/38 tooth counts for OEM spec, 32 tooth only for aftermarket. Schmidt says they have some 40s in testing under athletes, and their Force 1 rings run up to 54, so it’s not a stretch to think we’ll see bigger rings for more applications in the future.

And bigger chainrings are part of the story for their pro athletes. If they’re comfortable with the easy end of the cassette, they can go up 4 teeth on a chainring and keep about the same low end range on the new 50-tooth cog. But, now their top end just got way, way faster. Think 36-10 versus 32-10 when hammering down the straights and you can see why Nino might like this. And, it’s an ultra stiff chainring, they say there’s virtually no deflection even under insane power.


sram eagle 1x12 xx1 and x01 mountain bike group technical details

The design required a new chain design, too. That decision wasn’t just so they could make a proprietary part, it was because they needed to design it as a system to ensure proper shifting, retention and wear resistance. And, yes, it needed to be just a bit thinner.

Cassette cog spacing is 3.8mm on their 11-speed groups, but that shrinks to 3.65mm for Eagle’s 12 speed (with a slight bit more room between the smallest two cogs to accommodate the angle of the chain there). Chain width goes from 5.6mm on 11 speed to 5.25mm with 12 speed. The change in width isn’t really even important, it’s everything else they did to make it the best, strongest, quietest and smoothest chain. Ever.

sram eagle 1x12 xx1 and x01 mountain bike group technical details

“In order to fit (12 speeds) on bikes as they’re designed today, we had to go in and look at the chain,” said Schmidt. “At the same time, there’ve been advancements in chain manufacturing and design. Those advancements could have been applied to 10 or 11 speed or any other chain (but the investment of new machinery and tooling meant it made sense to apply it to this new group).”

sram eagle 1x12 xx1 and x01 mountain bike group technical details

sram eagle 1x12 xx1 and x01 mountain bike group technical details

A new chain manufacturing process was a massive investment for them, requiring all new tooling and machines at their German Portugal manufacturing plant. The sheets from which the chain plates are stamped start out flatter, and the more intensive plate shaping at the pin hole allows the pin to sit flush inside a chamfered hole. Completely flat material lets them perform more precise, consistent riveting, and that means the chain is less likely to fail because the plates are held in place more securely.

All told, there are 37 steps in each chain plate’s development. The panoramic spread above shows most of the process (click to enlarge). The changes from step to step are minimal, but each one is making slight changes to the shape of the pin holes and inside edges, and that’s the real secret to the new chain:

sram eagle 1x12 xx1 and x01 mountain bike group technical details

Called Smooth Link, the inside faces of the links no longer used angled chamfers. That feature was there to assist front shifting, but was no longer needed. And, in fact, they say was creating noise and hastening chainring wear because that chamfer would grind mud against the teeth.

The new design uses a constant radius on the inside face on both inner and outer links, which glides more smoothly onto and off of the teeth. That reduces noise and dramatically reduces chainring wear.

sram eagle 1x12 xx1 and x01 mountain bike group technical details

The small chamfer on the outside pin holes allow the pin to sit flush. As they’re pressed in, they fill in the chamfer to lock themselves into place. There was 0.1mm pin protrusion on the 11-speed chains, and now they’re down to zero protrusion. That’s a big part of how they were able to squeeze 12 speeds on the same XD Driver Body that their 11-speed cassette fit.

Roller width and dimensions have changed, too, and the inner plates and rollers all get a Hard Chrome treatment to increase their lifespan. The PVD Ti Nitride coatings protect them from rust and play a small role in friction reduction, too.

Put it all together and you end up with a system that runs quieter and smoother than anything they’ve done before, and it’s stronger, too. Win, win, win.


sram eagle 1x12 xx1 and x01 mountain bike group technical details

The X-Actuation trigger shifters look and feel mostly the same. The keep the Zero Loss cable pull method, adjustable thumb lever positioning and Matchmaker-X mounting compatibility.

sram eagle 1x12 xx1 and x01 mountain bike group technical details

XX1 uses a carbon top shell and trigger, X01’s body is all aluminum.

sram eagle 1x12 xx1 and x01 mountain bike group technical details

Inside, they made a few changes to make the system more robust and improve click feel. They also made the movements a little tighter, necessary to make the smaller movements precise enough for the tighter cog spacing.


sram eagle 1x12 xx1 and x01 mountain bike group technical details

The Eagle rear derailleur is functionally similar to its 11-speed counterpart, but there are a number of important upgrades hiding inside.

sram eagle 1x12 xx1 and x01 mountain bike group technical details

The B-knuckle has been updated to include an Igus bushing on the inside of the knuckle, which helps the derailleur move more smoothly through its range.

sram eagle 1x12 xx1 and x01 mountain bike group technical details

The mounting bolt gets a sleeve washer to prevent over tightening the derailleur to the hanger, which could end up causing it to bind up and limit movement. That also helps the system move easier.

sram eagle 1x12 xx1 and x01 mountain bike group technical details

The X-Sync lower pulley wheel has been upsized to 14 teeth compared to the 12-tooth upper wheel. The narrow/wide tooth patterns are there to aid chain management, particularly when cross chaining. The wheel is larger than before because, since there’s more chain wrap, allows for a longer chain to be used without increasing the length of the cage. That’s important because that 50-tooth monster needs a lot more chain, but they had to maintain enough ground clearance for it to be used on any bike (26″ wheels, anyone?).

sram eagle 1x12 xx1 and x01 mountain bike group technical details

Differences between models are: XX1 gets a carbon outer pulley cage plate and titanium and alloy hardware. X01’s cage is forged aluminum and it uses stainless steel hardware.

sram eagle 1x12 xx1 and x01 mountain bike group technical details

The derailleurs will ship with this installation guide. Marks on the upper wing align with the 50-tooth’s teeth to show how to set the tension screw for proper clearance between the cassette and upper pulley wheel.

sram eagle 1x12 xx1 and x01 mountain bike group technical details

The new Type 3 Roller Bearing Clutch gets a revised spring curve to keep pressure on the chain more consistent. The Cage Lock button has been moved back, out of the way, to reduce likelihood of damage in an accident.



SRAM has three testing standards for their cranks -XC, All Mountain and Gravity- and until Eagle, all were tested to meet their Gravity standards. That means an XC product like XX1 was completely overbuilt. With Eagle, they wanted to optimize the cranks more for XC, with differentiation between the XX1 and X01 cranks.

sram eagle 1x12 xx1 and x01 mountain bike group technical details

For XX1, that meant it didn’t need to handle the massive rock strike impacts of a DH crank, but it needed to have good long-term load handling. To save weight, they used a new hollow core construction, with a carbon layup that produced internal reliefs to save weight. It’s still overbuilt for what’s needed for pure XC -it’s tested to meet their All Mountain standard because they know people will ride it beyond XC- but it’s lighter than ever.

sram eagle 1x12 xx1 and x01 mountain bike group technical details

X01 gets a foam core instead of being hollow, with additional carbon laid up around the pedal insert to improve rock strike durability.

XX1 is about 30g lighter than X01, and the XX1 Eagle cranks are about 50g lighter than prior generation XX1/X01 cranks (they were the same, just had different decals). Yet they’re testing stronger than before, and SRAM’s reps say they’re testing stiffer than any other brands’ cranks in that weight class.

Another important upgrade is that these new cranks use the same chainring offset for both GXP and BB30 cranks, and the new Descendant cranks will fit it, too. There’s still Boost and Standard chainrings, but no more GXP vs. BB30 chainrings.
You can use the new Eagle chainrings on existing SRAM 11-speed GXP cranks, too, with the benefits being quieter operation and improved durability. Because it’s not using the new chain, retention will remain as good as before, no better, no worse.


Other than using Eagle chainrings on existing 11-speed groups, there is no cross compatibility. That means no mixing and matching other than being able to take advantage of the Eagle’s new chainring tooth profiles.

How quickly will Eagle trickle down? When they launched 2×10 groups in 2009, they released a new 2×10 group on an annual basis. With 1×10, that cycle sped up a bit because there were fewer parts to develop. For Eagle, we’re guessing we’ll see a similar cycle, but they say it’ll be based on OEM and rider demand.

There’s still a lot of full suspension bikes that are built with a front derailleur in mind, but Eagle eliminates that consideration. That removes all sorts of design limitations on tire clearance and pivot placement. It also allows the engineers to truly optimize suspension optimization around a smaller range of chainring tooth counts instead of needing to work well with anything from a 24 to a 38.

Why not go bigger with 13 or 14 speeds? Well, how different are you willing to go? At the moment, they believe consumer acceptance of a radically different design or need for alternate frame, wheel or other standards to accommodate a bigger cassette simple wouldn’t fly. After riding it, we can’t honestly imagine a need for more, but time will tell. There was a lot of off the cuff discussion about alternate transmission ideas, but that, too, requires acceptance of something radically new, both from consumers and the industry.

Will 12 speeds transition to road bikes? We didn’t ask specifically, but our guess is yes. Here’s why: Their new chain is amazing, so it’s only natural its technology will be spread across as much of their product line as possible. SRAM’s XD-R driver body for road bikes already has an additional space in there that would probably allow for a 12-speed cassette to be used without any change in wheel or frame design.

Up next, tech specs and actual weights…


  1. You know what, that’s far more sensible than I was expecting. SRAM being SRAM I was expecting the new 12sp stuff to need entirely new everything from hub drivers to axle spacing, but it doesn’t, bolt on and go. Of course being a luddite who’s just gone to 1×10 from 2×9 I won’t be using this stuff for a decade or so, but it looks nice all the same.

  2. That gold setup looks badass. I’m of course skeptical that they somehow made a narrower chain stronger, but i’ve not had any issues with my 11 speed chains yet so maybe there is hope.

    • The narrower chain being stronger makes sense to me. If the force applied is concentrated at the center of the pin, the length of your effort arm is decreased so the moment is decreased. Shear is likely the same as they didn’t remove any material around the pins but increased the contact area around the pins (which is huge for the way my chains have failed), and since they are machined more precisely, you’ll limit p-delta type wear. I don’t thing the surface area of the pins as they contact the teeth was ever a concern (I’ve never broke a chain by wearing out the pin). The weak spot for me has always been pulling a pin strait through a link. Everything about this (including making the chain more narrow), seems to help chain ware.

    • Narrower is stronger, as the potential torque from pin to pin increases with space. Of course that is under torsional or lateral forces which is always the case with chain breaks. Axial forces are pure shear on the pin and the STRENGHT is only dependant on pin diameter and the material shear modulus and has nothing to do with width. A wider chain will only be stronger under compression and a chain is never under such stress regime.

  3. “The complexity of a front derailleur”. Never has such a ridiculous statement been used as reasoning to push a product. Sorry, I learned how to use a FD within my first week of riding a bike, and probably a couple more weeks to figure out gear ratios and when to use what gear. I just don’t understand this argument of “simplicity”, other than the setup is simple. But actually using the bike with a 2x drivetrain is not rocket surgery…

    • Just let me clarify that I am not against 1x, but stop insulting even halfway decent riders by saying how difficult a FD is to use.

      • You’re right on the money- any schmuck can learn how to use a FD within minutes of riding, and within a few days, one understands how to combine it with rear shifts. I like 1x also, but find the argument really dumb.

    • The complexity of the front derailleur goes beyond pushing a button. Why do you think increasingly fewer bikes are supporting front derailleurs? Because they are a pain in the ass to design around.

      • Front derailleurs require frame and tyre clearance thus limiting design optimisation on modern bikes with bigger wheels. Get rid of the FD and you open up design freedom. I’m happy they’re eliminating the FD from the MTB. Its just a mud trap and I’ve been happier without it since I went 1×11.

    • It’s aimed at the gravity crowd, the XC race crowd, and (god I hate myself for using this word) “enduro”. Those people like, and need simplicity. Your cockpit on an enduro bike is simple. You have two brakes, one shifter, and one dropper post lever. Adding in a front shifter messes with that. When you are absolutely pinned, gassed, and staring at a hill that suddenly popped up in front of you, messing with a FD is truly too complex (unless you have Di2 2x with just the one shifter).

      The other issue with FD complexity is frame design. Having to account for a useable FD sucks when you want to make an aggressive longer travel bike. It wreaks havoc with suspension optimization. The majority of new 160mm+ bikes aren’t FD compatible for good reasons.

    • Ignoring the simplicity of thinking that only the simplicity of the end user is of concern, the ‘rocket surgery’ mixed proverb is priceless!

  4. While I can appreciate SRAM doubling-down on their 1x system(s), I still think that the jumps between gears are too big as it is currently, and this will be even worse. Yes, the overall range is admittedly impressive, but for me PERSONALLY, I’d rather have a 2x (or 1x even) and an 11-36 11sp cassette. But I’m also more of an XC racer. I guess my point is that this isn’t the best choice for everyone and is extremely specific to the rider and the region.

    • Not worse. Its the same as the existing 10-42, but with a 50 added on the end, so you’ve got the same jumps as current 1×11.

      • The count on an 11-36 is 11-13-15-17-19-21-24-28-32-36
        The count on a 10-50 is 10-12-14-16-18-21-24-28-32-36-42-50

        For the top half of the 10 speed cassette, its identical. Below that it’s only fractions different due to starting at 10t instead of 11t. Then at the top 2 the jumps get a bit more aggressive. But TBH, those aren’t your primary gears, so a 16-20% jump in cadence isnt a big deal.

    • The jumps on the 10-42 are already too big! Going from the 36 to 42 is a major difference, now you go from 42 to a road chainring. Spinners are winners I guess.

      Shimano came out with this idea years ago… they call it mega range.

      • For its intents and purposes, it works really well. Now if you are a triathlete or TT rider trying to optimize energy/cadence/power…then yes, tighter ratios are advantageous, and I’d imagine they’ll come out with an XD cassette that will work with something like a 54 ring up front, and go 12 speeds (say 10-36) with tighter ratios, and I’d definitely run that on a TT bike. On a mountain bike, the terrain is all over the place. You’ve got varying soil with different amounts of traction, you’ve got variable grades even while climbing, and you’ve got obstacles to get over. If you are riding on a mountain bike on actual mountain trails, trying to precisely optimize your cadence is a lost cause because as soon as you are dialed the soil or terrain will throw you off.

        • Sam’s answer was spot on, I just wanted to add this: tightly spaced cassettes in mountain bikes don’t make much sense because when you have to face a sudden change in elevation (such as coming off a downhill section and facing an uphill ramp) you’d have to go through too many gears to find the right ratio. This is even true when talking about double or triple chainrings.

  5. Part of me was hoping they’d just take the sex appeal out of it and make a nicer Dual Drive system. They already make a 1x system that can be spec’ed with well over 600% range, so why not make the most of it?

    • Steve fix the creak in the cassette with wax lube. Remove the cassette and lock ring. Clean it up. then pour wax lube between the 12T sprocket and the lockring cylinder that runs to the start of the thread. The creaking stems from corrossion between the steel cassette body and the aluminium lockring cylinder/carrier

  6. I say let’s get rid of spokes and run a giant cassette wheel!

    Joking aside, I have tire clearance issues with my xt 11 spd 1x. I haven’t checked cassette spacing and chainlines between the groups, so maybe sram is okay.

    I do think the whole “optimal chainline” thing is kind of overblown though (ala Spesh SCS), as they apparently can just slap more rings on there. Anyway, I’ll never buy this as I can ride what I have and they already told me 1×13 or 1×14 is possible. I may get rid of all my 2x road and 1x mtb set-ups if someone actually has the balls to drop a 1×14 that works. A 44 chainring on a 10-38cassette meets all my range. 14x would give 2 tooth jumps on average, which could be skewed to 1 tooth jumps on the smaller end where the % change is larger.

    • BTW – that 44 chainring on a 10t-38t cassette is for road. My existing 1x on mtb works fine. If I spin out a 30×11 combo, I’m already going too fast for my mixed use technical trails. Riding to trails can be an issue, but not enough to really bother me.

  7. “Eagle is substantially lighter than a 2x”: complete bullsh*t, the cassette is heavier than 1040, use a 26-36 and you add 50 grams for the small chain ring, use Di2 and all you have is the 100 gram extra of the front derailleur.

    • “Use Di2”.

      Okay, I went from a 2x Di2 to a 1x Di2. FD: 111g per Shimano. Front Shifter: 64g per Shimano. Cabling: about 30g per my scale. XTR 11-40 cassette is 327g, XX1 is 268g per SRAM, so another 59g reduction there.

      Total weight loss is 264g, or a little over half a pound. In the drivetrain. That’s not small.

      The only thing “bullsh*t” here is your math skills.

    • of the front derailleur…and the front shifter and the cable and the housing. your angry math has some holes Sir

  8. I don’t think the implication is that the FD is “complex” due to being difficult to use; I think it has to do with how unsuccessful most people are making them work efficiently, effectively, and quietly.

    I am for anything that gets rid of the FD, which only about 0.5% of the bike-riding population can properly adjust so that it doesn’t sound like a gaggle of drunk grasshoppers coming up behind you on a climb.

    For most people, a noisy drivetrain doesn’t bother them. These are the same people who have year-old coffee stains in their car’s floormats; who wear flannel to weddings; who walk around in mismatched socks. They just don’t care. And that’s okay.

    Others are more fastidious about their lives, and the sound of a chain rubbing on the inside of the FD cage is right there with nails on the chalkboard.

    Bye FD. Good riddance.

    • People for whom others’ FD noises are as annoying as nails on a chalkboard are in a minority far smaller than .5%, I believe.

    • “Bye FD”, signed SRAM. Because that’s the only company that’s giving up on it. There is exactly a 0% chance Shimano gives up 2x. Ze-ro.

      Key is to “most people” it’s not a big deal. My personal pet peeve is noisy chains and RD pulleys, but most people don’t seem to care. The solution is not to get rid of them, it’s to learn how to maintain your bike. But to say everything should and will be going to 1x because of how uber complicated it is to operate, and that they make noise is just hilarious. I mean, hell, if the FD is just soooo complicated to use, and adjust, why not give everyone a Landrider bike with Autoshift(TM), and no one has to worry about shifting at all!

  9. Somebody please medicate the industry for a few seasons.
    I read that when the laser was created somebody said it was a solution looking for a problem.
    Seem to be many solutions being created by this industry lately.

    Probably my age talking but I’m sick of it. Too much new, too fast, too often.
    One more mini step (possibly) forward so someone can drive to the trailhead for a short lap.

    • You’ve hit the nail on the head – that people said the laser was a solution looking for a problem is indicative of their narrow mindedness. After all optic fibre, bloodless surgery, cutting, welding, spectroscopy, bar codes, thermometers, CNC machining etc. ad nauseam are all marketing hype to sell the laser no-one needed.

      • So true. The article I read was very clear about the many many uses for a laser that are now common place. And one day I’ll look at the 1x of the future and will think…. What was I so concerned about?

  10. Adding range and refining an already great shifting platform. Sounds good to me.

    Everyone that’s hating now will be riding either this platform, or something similar put out by a competitor in the next couple years (if not sooner).

    Stop trolling and look at the positives instead of finding something to complain about. If it’s not beneficial to your riding style.. awesome. Crack a beer and watch some mountain biking edits, or better yet.. go take a spin through your local trail.

  11. Interesting. As a guy who rides the road to super steep the trails, I need range. Heck, I spin out regularly on my 1x snow bike.

    And what about Grip Shift? Honestly, if I wanted triggers, I’d probably ride full Shimano instead of SRAM with XTR brakes.

  12. My 2×10 has wider range, tighter jumps, and shifts perfectly. Of course it’s Shimano. SRAM never did nail the FD. I highly doubt the 2x systems are going the 3x route. 1x is great for some people and applications but not nearly all, especially XC regular Joe’s like me.

  13. I applaud SRAM for innovation/ evolution- they’re a great concept/ buzz word/ PR company and successful because of those strategies. However, their tech “advances” seem to always come with major compomises: 1x demands crazy cross chaining in many gears (chain wear), high chain tension (friction), and the movement of more and more mass to the suspended parts of a full suspension MTB. Motorsports engineers do everything possible to minimize the weight of wheels and suspension components in order to create suspension systems that are more active. We want the same from MTB suspensions, but moving more weight to the cassette and rear der makes this more difficult. Owned XX1, loved the look but hated the drag, gear gaps, and endless thumb shifting to get a widely different gear. Love my XTR 2x for racing in Colorado. Front shifting is great for powering through quickly changing terrain. Still, it’s nice to have choices…

    • This is a good comment. I run Shimano’s XT 11spd 1x on my mtb (also CO front range). I notice the extra drag/noise in my sadly often used 42t cog on climbs. I can deal with it on my mtb. For road, I am not sure I’d want this. My campy FD is easily trimmed to be silent even if I am stupidly crossed up. My wife’s Shimano road – same. And one can tell a smoothness differences running on your larger ring on road, compared to the small (but I’ll admit that may be in my head)

  14. Can you clarify the bit about them removing the chamfer from the inside of the chain links, as those outer links still look heavily chamfered? Thanks.

  15. I’d like to see another cassette option or two. Maybe a 10-42 and a 10-46+ in 12 speed. If you can manage your 10-42 but want a tiny bit more, you don’t need a 50t

    • I think the intent is one could run a larger chainring, extended high range. The % jump from 42 to 50 is similar to 36 to 42.

      • More people need the low than the high. Some people need a bit of both. This provides that. You gain weight with a bigger ring but you also improve wear, assuming that bigger ring doesn’t force you to the top of the cassette all the time

        • Yep, more people need low, but to get there they lose a LOT of high end on a 1x system (compared to 2x). This solves that, so people can throw that 28t chainring on an not spin out everywhere but the ups. If high end wasn’t an issue, 2x wouldn’t exist.

  16. This looks pretty cool. The gold color is unbelievably hideous, but I imagine that will go away and we’ll see normal colors like silver and black before too long. A nice 12 speed 11-36 or 11-40 spread on a 1X road group would be cool.

    • Im running 40cassette on many of my road wheelsets with no probs though brah. Even Lightweight wheels handle it no probs. My Zipp 202 disc no probs.

      I can everest terrain nobody else yet has and do it with ease and relative fresh legs the next day.

  17. I doubt 12 speed will trickle to the road groups. The key difference is that the 12 speed cassette uses the dish of the wheels drives side spokes to access clearance for the derailleur when on the 50T sprocket. On a road cassette even with a 32 there is not sufficient space since the sprocket is still relatively close to the hub centre.
    In the mean time just get my Red E-Tap and Eagle XO1 12 ASAP. I’m loving what I’m seeing coming from SRAM

  18. Eagle is interesting but I’d rather they make a pro dd3 (2s IGH instead of 3s IGH) to get even more massive range. Or a 14s IGH to compete with Rohloff.

  19. Personally I think the SRAM 1 x11 groups are great. A 1×12 is another great option. I’ve recently put 1×11 XTR M9000 groups sets on two MTBs and have had to remove and sell them because they just are not as good as SRAM 1×11 XX1 and I got sick to the back teeth of creaky Shimano cassettes.

    SRAM is convenient on all fronts – e.g. direct mount chain-rings.

    The SRAM cassette is a fit and forget. No issues with damage to the XD driver etc. No issues with creaking.

    SRAM innovate. Shimano not so much – a trickle down (from road spec) electronic groupset is not innovation

    I just wish SRAM would stop using DOT fluid and then I could rid myself of shimano brakes.

  20. I think it’s funny how the FD is now considered a technology pariah. Perhaps this was caused by decades worth of suppressed frustration in how pushing a FD shifter made the drivetrain shift opposite of the rear.
    Up next is “tech specs and actual weights…” But I’m still waiting to see how much that cassette is going to cost. Since I didn’t withhold enough taxes this year and have to pay the IRS, need to rob from my 401K or refinance the house I suspect…
    @RCR, why the comment about DOT brake fluid? Seems to do pretty well for a bazillion motorized vehicles out there.

  21. I don’t really get the hate on new technology here – this is BikeRumor, not Vintage Bicycle Quarterly, and even VBQ embraces some new tech. If you don’t want to read about the vanguard of the bicycle industry, then just keep riding your steel bike with 8 speed (or 5, or 1) and friction shifters. I do! New tech doesn’t make your existing bike go away or work poorly, except sometimes relative to new tech.

    Also, if you truly hate 1x, run Shimano! They clearly still love FDs. I don’t even own a 1x bike, so I’m not any kind of evangelist.

    My question when thinking about 1x tech being prioritized, especially by SRAM, is this: If you were starting from scratch to build the best drivetrain using modern manufacturing and technology, why would you bother with engineering two separate shifting systems if you could spend the time and resources optimizing one? SRAM’s approach to 1x seems to be embracing the second of those two philosophies, which makes sense to me. If we can get the same range from a simpler (overall) system, why not?

    • This!! Avidpsychlist makes excellent points.

      I don’t get the hate either… This is innovation, you don’t have to like it or buy it, but in the big picture innovation always moves us in a forward direction. Knowing only that, this article should create excitement, I would think… Especially with the general improvements like the chainring and chain which can improve drivetrains outside this 1×12 concept.

      I have a SRAM 1x (converted from 2x) and a Shimano 3x, and all have their strengths and weaknesses, as with most things. I do find that 1x with dropper post and/or suspension lock on the left is easier to control when I’m in an instinctive riding mode, so that’s become my preference. But that’s all it comes down to – everyone can buy and build to their heart’s content. This 1×12 provides another option, and I like that.

  22. There is a lot of hate for something new and innovative. Everyone wants to compare Shimano vs Sram and declare a winner. They are both great companies and I applaud Sram for the innovated tech on this and if they want to box it next year with 13 gears and etap then I am all for it. If you don’t need the Eagle system then why be a hater. Enjoy your bike and feel lucky that these options are available even if their value is important or not to you at this time.

  23. Horses for Courses… I love 1x, I haven’t had a FD on a bike since 2008, including Gravel Grinders, city commuters and cargo/grocery bikes. Props to SRAM for advancing 1x technology , they will continue to get my money.

  24. I have a group xx1 working perfectly in my fatbike, but the range is not enough for me. I am excited with the possibilities of the 12 speeds, but I want to throw a question:

    If I install a new chainring (XX1 or XO1 12-s) on my current XX1 cranks (actually with 11-s chainring), and install the new components X01 Eagle or XX1 Eagle 12-s (chain, derailleur and cassette), it should work properly. What do think about?

  25. When are we going to get past this ancient technology? You could buy a gear hub with this sort of range and always have reliable shifting. No need to dish your wheel to the extreme, shifting quality doesn’t depend on chain wear, instantly select any gear. With a 12spd derailleur all the tolerances are smaller so when the parts wear, the shifting becomes unreliable, in common with every derailleur system. Replacement chain alone is £60 currently…

COMMENT HERE: (For best results, log in through Wordpress or your social media account. Anonymous/fake email comments may be unapproved or deleted. ALL first-time commenter's posts are held for moderation. Check our Comment Policy for full details.)

This site uses Akismet to reduce spam. Learn how your comment data is processed.