Dirt Rag Magazine

First Look: SRAM Eagle 1×12 drivetrains, XX1 and X01


That is it. The rumored 1×12 speed drivetrain from SRAM. Actually that is one of two. Above is the new XX1, which is aimed at cross-country racing. Below is X01, for enduro racing and trail riding (we didn’t get a nice drivetrain shot of this one).

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XX1 Eagle

Crank – $425


The cranks get the lighter and stiffer treatment and a new tooth profile. The updated narrow/wide teeth are designed to retain the chain better as the chainring wears, and run more quietly. Chainrings options are 30-38 in two-tooth increments.

Cassette – $420

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The one-piece machined cassette now has 11 steel cogs, with the big 50 tooth cog out of aluminum. It certainly isn’t cheap, but now you can show off your blingy cassette with the optional gold finish. Tooth profiles are revised to go with the new chain, and promise better shifting. The 10-50 range is 500%, which covers the same range as most 2×11 drivetrains.

Shifter  $162


Internal improvements promise better feel, durability and precision. You want Grip Shift? You can have it!

GripShift – $148


Derailleur – $289


A new mounting system, improved clutch and a 14 tooth lower pulley keeps things compact, smooth and tight.

Chain – $60-85

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There is a single chain for both X01 and XX1.  SRAM covers this well:

“It might look normal from the outside, but the engineering inside this incredible new chain design that makes possible a gear range previously found only in 2-chainring drivetrains. And it’s also the biggest contributor to the Eagle™ drivetrain’s ultra-smooth, precise, durable and quiet performance. The Eagle™ chain’s links have a smooth radius, with no sharp edges or chamfers, which yield a significant reduction in noise, friction and wear on chainrings and cassette cogs. This design also allows for a flatter plate, which means more consistent chain riveting and greater overall strength. HARD CHROME™ technology extends the chain’s optimal performance life, and a Titanium Nitride coating on the Gold and Black models decreases corrosion and further reduces friction.”


Other than the foam core in the XO1 crank, there is little functional difference between the XO1 and XX1 groups. All parts interchange, and as stated above, they even share a chain. The foam core in the crank claims to increase impact resistance and prevent pedal pull-out. The XO1 crank is tested to SRAM’s downhill standard, so going big should not be a problem.

Crank – $390


Cassette – $360


Trigger Shifter – $127   Grip Shift $118

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Derailleur – $220

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Our Take

Does this really mean the death of the front derailleur for mountain bikes? Not really. It probably does put another nail in the coffin. Trying to cram suspension pivots, 3 inch tires and two chainrings into the same spot, something had to give, and the front derailleur was the most likely candidate. Don’t worry, you’ll still be able to get all the bits needed to keep your double or triple crank drivetrain running for years to come, but when it comes to high-performance mountain bikes, the front derailleur is going the way of the dodo bird.

More info at SRAM’s website.


Trail Tested: SRAM X1 Drivetrain


Until the very recent release of the new GX group (which also offers multiple chainring options if you go that way), SRAM’s X1 drivetrain was the company’s entry level, full mountain bike, 1×11 offering. Whether you’re a cross-country, trail or all-mountain rider, this X1 group is a great way to get a taste of wide-ratio 1x philosophy.

Since last fall, I’ve been riding both this X1 group and the top-tier XX1 in a combination of dry and wet conditions. There have been some winter rides with questionable trail conditions, but as guilt crept in, I told myself it was all for the review. The X1 group has fared great and despite the sometimes peanut-butter-like mud I’ve encountered, I haven’t noticed a distinct difference in performance between the two drives.

Although, there is a difference in feel because of the design of the shifters. The X1’s trigger and shifter body have a different shape than the more expensive X01 and XX1 models. The X1 shifter body is aluminum and slightly larger versus the more compact carbon body of the XX1 shifter. Every SRAM 1x shifter features Matchmaker compatibility to direct-mount on SRAM brake levers and ZeroLoss engagement where the shifter begins to move cable instantaneously as it is pressed. How- ever, the X1 does not have the trigger-angle modification for rotational adjustment of the larger downshift lever. Even though the larger X1 trigger sticks out farther than the XX1 trigger, it still feels smooth and quick.

I don’t think the shifting action is any less fluid, but feedback from the trigger seems softer. The X1 trigger is not as crisp and precise-feeling as the XX1. The input I get in action on the trail is different, but the function isn’t any less effective.

The cassette remains the most expensive item in the drive and the biggest hurdle for those looking to try 1×11. However, it’s hard to argue against the X1 X-Horizon rear derailleur and cassette. When considering price per grams compared to almost indistinguishable differences in performance, it makes the X1 rear components great options for those looking for more-affordable 11-speed options. There is about a 55-gram weight savings with the pricey XX1 cassette, but the reduced weight comes at a cost of almost $2 per gram. All of SRAM’s 10/42 1x cassettes require the XD driver body on the rear wheel. Mechanically there is little difference between the three SRAM 1x derailleurs other than cage materials.


The X1 1400 hollow-forged crankset is where you’ll find the most significant weight difference. The aluminum 1400 cranks with a 32-tooth chainring are 800 grams. It’s roughly one third of a pound heavier than the XX1 crankset. There are fewer chainring options for the X1 spider as well (30, 32, 34, 36, 38), but most trail riders are going to be in the 30 to 34 range anyway, and they all feature the alternating tooth profiles we’re familiar with for 1x drives. The bolt-on spider system does allow you to use other chainring options, including the new Direct Mount chainrings from SRAM or any number of alternatives from aftermarket companies that cover a huge range from 26 to 40 teeth. There are two less-expensive X1 cranks as well, the 1200 and 1000, which are heavier but lack the bolt-on spider of the 1400.

So do I think X01 or XX1 are worth the higher price tags? I would pay more for the shifter. I like the trigger feel of the higher-end models; the ergonomics and crispness of the XX1 triggers are worth the investment to me. But as for the rest of the group, there isn’t a noticeable enough difference in performance to justify the other upgrades, in my opinion. The X1 group looks great and performs well. If you are looking to give 1x a try and don’t mind the extra grams, this drivetrain won’t let you down.

Vital stats

  • X1 1400 crankset: 800 grams w/bottom bracket, $262
  • X1 shifter: 121 grams, $81
  • X1 rear derailleur: 256 grams, $231
  • XG-11800 casssette: 315 grams, $313
  • PC-X1 chain: 258 grams (114 links), $37



SRAM unveils 7-speed XO1 downhill drivetrain


With the drive forward to stuff ever more gears onto rear hubs, it is nice to see SRAM take a step back and create a group with less gears simply because that is what makes the most sense for the application.

The real key to this system is the new 7-speed X-Dome mini-block cassette in a 10-24 range. Most downhill bikes are equipped with road-geared cassettes with something like a 12-26 range and 10 speeds. While this was plenty of range for a downhill bike, the tight gear ratios meant often shifting two or three gears at once to get to the desired ratio.


A similar range, with less gears means bigger jumps between gears and less shifting. Many riders of XX1 and X01 11-speed groups (with the 10-42 cassette) have discovered the same thing, that these larger jumps between gears is actually better suited to the way most people ride. This setup only works with the XD cassette body from the X01 and XX1 11 speed groups.

Read more about the new drivetrain here.


SRAM XX1 | Enduro | Part 2: Flat Out and Focused

This second chapter follows the best enduro racers in the world from the iconic Mega Avalanche in Alpe d’Huez to the final race of the Enduro World Series in Finale Ligure, Italy. Here, in addition to Jerome Clementz’s victory in both the race and overall, Curtis Keene, Rene Wildhaber, Anka Martin, Anneke Beerten and many more reflect on the first season of the Enduro World Series and what it means to be an enduro racer today.

See Part 1 here.

Click here to see a photo gallery by Sven Martin.

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