Since the announcement of NX Eagle, almost a year ago, we’ve seen the release of the ultra high-end electronic Eagle AXS systems. With these sort of components more often than not making the headlines, it's good to remind ourselves that SRAM is cognisant of the everyday rider and their budgets. That said, entering the world of 12-speed is still a fair investment but consider that the entire NX Eagle groupset costs less than an XX1 Eagle cassette on its own.
In comparison to the early(ish) one-by systems I mucked about with in the past, the Eagle systems (including NX Eagle) are simply brilliant. I started off with a bodged together 1x9 configuration which, in hindsight, was pretty terrible. The progression to 10 speed and a clutch derailleur helped somewhat. I finally got the taste of 11-speed luxury with a SRAM NX upgrade kit and later I moved onto the GX version. At the time, I was fairly convinced that 11-speed covered my needs. But (as should be expected really) the new 12-speed Eagle platform quickly changed my mind, with the utility of the additional range quickly becoming apparent.
Diving into the differences
The NX Eagle groupset is largely similar to the more expensive Eagle groupsets. The big difference is the materials used in construction along with more efficient manufacturing techniques taking up less machine time. Where the more expensive Eagle components use carbon and aluminium, NX Eagle uses steel and plastic and bearings are replaced with bushing. This makes that NX Eagle heavier but the underpinning technology remains largely the same, with almost indistinguishable functioning out on the trail. The material difference with the NX Eagle groupset, however, is the cassette.
With the demise of the double, or even triple chainring, the cassette is the heart of the groupset. So it is important to note that the NX Eagle cassette (much like the NX 11-speed cassette) differs from the rest of the Eagle family in two ways: 1) the gear range and 2) the freehub body interface.
The Eagle XX1, X01, and GX cassettes all have a a gear spread starting at 10 tooth up to the near dinner plate sized 50 tooth. The NX Eagle cassette has a larger 11 tooth cog while maintaining the large 50 tooth biggest cog. One tooth might not sound like much but the difference is a 454.5% range on the NX Eagle cassette versus a 500% range on the other Eagle cassettes.
A benefit of the larger 11 tooth cog is that the Eagle NX cassette can accommodate a normal spline (Shimano-type) freehub body. All other Eagle cassettes require SRAM’s XD Driver system. This results in additional costs for riders needing to adapt their existing hub from a spline type to an XD Driver. This is one way that NX Eagle helps to reduce the costs of upgrading to 12-speed. As the XD Driver Body is hub brand specific, it cannot be included as a part in the groupset.
The NX Eagle cassette is fairly heavy at 614 grams. That is a result of the materials used and cost effective construction techniques. The NX Eagle cassette is pieced together from 12 stamped steel cogs. The largest four cogs are then riveted to an aluminium spider with the remaining cogs sliding onto the freehub and separated by spacers. A lockring holds all the cogs in place. Because of this bulkier construction and the use of steel for all cogs, the NX Eagle cassette is the only cassette in the Eagle range that SRAM a confident for use on ebikes.
The cranks and gears
The NX Eagle cranks are shaped from 6000 series aluminium, where GX Eagle uses the higher grade 7000 series. The cranks are designed for direct mounted chainrings, specifically SRAM’s own X-Sync 2 chainring which is held in place by three Torx bolts. The crankset pairs with SRAM’s Dub bottom bracket (generally not included in the groupset bundle) which is compatible with most frames. The chainring is stamped from steel and features all the same Eagle technology including the kinked tooth profile to improve chain retention.
Likewise, the derailleur is packed with all the same features found further up the Eagle range. The same straight parallelogram design featuring a roller bearing clutch to keep the chain tight and the cage lock to hold the derailleur out of harm's way when removing the back wheel. The Eagle shifter lever is plastic compared to the carbon one found at the top of the range and it rotates on a bushing versus a bearing. Interestingly, the NX Eagle shifter is the lightest shifter in the Eagle range. The NX Eagle chain uses a heavier solid pin construction.
Aside from the cassette and the freehub body requirements, NX Eagle is fully interchangeable with components across the Eagle family. This is convenient for mixing and matching while dipping into another Eagle range for a specific component when it makes sense.
For example, if I were upgrading to NX Eagle under my own steam, I’d have taken advantage of this cross-compatibility. My bike already has an XD Drive freehub body, as I have a GX 11-speed drivetrain fitted. So hunting for a splined freehub body makes little sense when I could spend that additional money on a GX Eagle cassette with the full 10-50T range while still benefiting from the cost saving of NX Eagle through the rest of the groupset.
You can see a comparison of the claimed weights of each component across the SRAM Eagle family compared to the NX Eagle groupset, along with the real-life weights from our review parts below:
Weight comparison across the SRAM Eagle family (in grams):
SRAM NX Eagle Claimed Weights vs Our Measurements (in grams):
The pricing for the NX Eagle groupset and upgrade kit varies from retailer to retailer. But it seems that without any sort of discount, a complete NX Eagle groupset is priced at around R6,500 while the upgrade kit is approximately R5,000. The upgrade kit includes the cassette, derailleur, chain, and shifter, excluding the crankset with chainring.
Riding Eagle NX
I've had the Eagle NX groupset on my Pyga Stage for just over three months. It is the same bike that I tested the GX Eagle system on a few years ago. When not sporting test drivetrains, the bike is dressed in 11-speed GX.
I notice very little difference between the general performance and shifting between NX Eagle and GX Eagle groupsets. From my experience with XX1 and X01 Eagle on other bikes, the feel of the shifter is a little more premium to the touch (the plastic NX Eagle shifter gives it away) but there is little to distinguish them at their main task, changing gears. Weight is really the defining difference between the Eagle families and, of course, the slightly reduced gear range of the NX Eagle cassette.
Over the three months of testing, the NX Eagle groupset has functioned flawlessly. The only maintenance required was a twist or two of the barrel adjuster to accommodate the stretching of the new cable. Otherwise, the shifter developed no play and the derailleur remained crisp and accurate. SRAM’s chain retention is renowned and NX Eagle did not disappoint, with clatter and noise kept mostly underwraps.
The test groupset arrived with a 32 tooth chainring. I understand that for many riders this might be the optimal size but, for me, sizing up to a 34 tooth chainring would better suit my riding. Furthermore, if you consider that NX Eagle lacks the smaller 10 tooth cog on the cassette, you’re going to need some added grunt if you plan to power along dirt road at any considerable speed in the 11 tooth.
The NX Eagle groupset offers a 12-speed entry point that competes in features and functionality with groupsets twice the price. While NX Eagle performances flawlessly, there are two obvious compromises with the lower price tag: weight and gear range. As a fan of brands trying to bring their high-end technology to a broader market, the Eagle NX groupset certainly opens up more options.