Wil hands-on with the new SRAM GX AXS groupset
The robots are back! What you see here is the newest mountain bike drivetrain – the SRAM GX AXS. Two years after launching their flagship XX1 and X01 Eagle AXS groupsets, SRAM has now phased out its wireless AXS technology to the more accessible GX Eagle level and, as expected, is priced atquitemore attractive.
To clarify, this isn't an entirely new kit. SRAM just joined the ranks with the introduction of the GX AXS derailleur and GX AXS controller (shifter)Latest GX Eagle Mechanical Drivetrain. You will be able to get the new GX AXS components individually, as an entire kit or as an upgrade kit.
how much does it cost?
The SRAM GX AXS upgrade kit is listed at AU$904, which is pretty impressive and almost half the price of the XX1 AXS. In this upgrade kit you get a shifter, derailleur, battery, charger and chain clearance tool. Below is a pricing comparison with XX1/X01 equivalents;
- SRAM GX AXS upgrade kit: AU$904
- SRAM X01 AXS upgrade kit: AU$1,399.95
- SRAM XX1 AXS upgrade kit: AU$1,699.95
Of course, as with any SRAM Eagle 1×12 drivetrain, components can be mixed and matched. So you can pair GX AXS shifters with XX1 AXS derailleurs and run them with an X01 cassette and NX Eagle chain. It's worth noting that you can also buy the GX AXS shifters ($226) and GX AXS derailleurs ($558) separately. However, the standalone transmission does not include the necessary AXS battery.
So what's the difference?
Functionally, the SRAM GX AXSzipperandHurrahJust like the pricier XX1 and X01 Eagle AXS components. In fact, the key electronic components - batteries, motors and switches - are the same. However, the use of less exotic materials elsewhere can help make the wireless shifting technology significantly less expensive.
The main difference is the derailleur cage, which is made of steel instead of alloy (X01) or carbon (XX1). You also get regular steel hardware instead of the titanium adjustment screws used on the XX1 mech. Otherwise that's it.
Oh, and see that funky vent cover on the back of the derailleur? It's a new plastic clip-on cover designed to provide more protection for the battery underneath. It is included with GX AXS derailleurs and is also mechanically compatible with XX1 and X01 AXS. SRAM will sell it as an optional accessory for AU$30, which seems like a lot of money for a fairly simple piece of plastic.
what about the weight
The GX AXS is heavier than its more expensive sibling, and it's also slightly thicker than the mechanical GX Eagle. If we're just comparing the shifter, derailleur and associated cables, it's 62g heavier than the mechanical option (532g vs 470g confirmed).
When you break down those weights, you'll actually find that the minimalist GX AXS shifter is surprisingly light at 68 grams. Compared to a mechanical GX Eagle shifter with cable, the latter weighs 170 grams.
However, GX AXS derailleurs are significantly heavier than mechanical ones. Including the battery, the rear derailleur weighs 464 grams on our workshop scale. That's 164 grams heavier than the mechanical GX Eagle derailleur (300 grams). I mention this because some riders are particularly sensitive to the weight of the rear axle suspension, and we suspect that there will be plenty of mechanical XX1/X01 owners who will be interested in the GX AXS upgrade kit.
For those riders, here's a quick weight comparison with some SRAM 12-speed options, in order from lightest to heaviest;
- XX1 Eagle derailleur: 265g
- GX Eagle derailleur: 300g
- XX1 Eagle AXS derailleur: 375 grams
- GX Eagle AXS derailleur: 464g
Granted, the GX AXS is a bit bulky compared to these alternatives. if we're talking aboutalldrivetrain, then the GX Eagle cassette and crank options also have a decent amount of mass. Therefore, a higher-end kit will better meet real weight needs.
Setup SRAM GX AXS
But it's not all about weight. Of course, one of the most attractive aspects of the AXS wireless system is that you completely eliminate the need for cables, which not only makes for a pleasingly clean setup, but also makes for the easiest installation process ever.
I've installed a GX AXS drivetrain on two test bikes -My Kotick BFeMAXMore recently, there has also been a custom Specialized Chisel (more bikes coming soon to this one). The BFeMAX uses external cable routing (FYI, totally underrated), so setting up a conventional mechanical drivetrain is hardly a pain in the ass. Chisel, on the other hand, uses internal cable routing. Instead of fiddling with foam tubes and tiny ports for running cables through the downtube, bolting on the GX AXS derailleur and shifters couldn't be easier, though.
This derailleur is officially compatible with SRAM's 10-50T and 10-52T options. I haven't tried it with a Shimano 12 speed cassette, but it's worth noting that others have had success elsewhere with the Shmeagle™ setup. Of course, neither SRAM nor Shimano would endorse this inbred configuration. I did a full test, setting up the GX AXS derailleur with a 10-52T GX Eagle cassette, chain and alloy crankset.
On the other end, the shifter can be mounted to the handlebar with its own separate clamp, or directly to the MatchMaker clamp on the SRAM brake lever. From here, it's just a quick pairing process to get the shifters talking to the derailleurs (check outSRAM's videoGet the handy AXS Installation Guide).
As with any Eagle derailleur, getting the correct chain length and setting the B tension correctly is critical to proper shifting performance. To help set B-tension, SRAM includes a plastic guide in the GX AXS upgrade kit. Move the chain into the second largest cog, then use the guide to keep the upper guide wheel the correct distance from the cassette. If you have a full-suspension bike, you need to set the rear shock to sag.
Another important note is that once you've set the derailleur, you'll want to make sure the limit screw is backed up a bit. SRAM recommends turning them back a 1/4 turn, this will keep the motor from clashing with the limit screw and potentially burning itself (this was an issue we had)has a dedicated epiclast year).
How was the performance on the track?
I honestly find it indistinguishable from its XX1 and X01 AXS counterparts. Overall performance is excellent, with the lovely light action of the AXS shifter providing near-instantaneous shifts to the rear mechanicals. On short rides less thumb force is required to initiate the shift, which is fine, but on longer rides the difference from the cable drive setup becomes quite noticeable - marathon runners and big-day trail riders will Appreciate this.
If we're talking about the overall performance of the entire drivetrain, the GX Eagle cassette isn't as meticulously machined as the pricier XX1/X01 cassettes. As a result, the chain cannot slide seamlessly from one cog to another, especially under stress. However, mount a GX AXS derailleur to an XX1/X01 cassette with a matching chain and the performance gap disappears. In fact, that's probably the setup I was looking for - instead of spending money on a full X01 AXS drivetrain, I just paired the GX AXS shifters and derailleurs with the X01 cassette and chain. You'll save around 600kg on the derailleur for only 76g less weight while enjoying the same shifting quality.
In addition to the clutter-free cockpit, it's nice to have one less cable to manage and the potential for noise. I also like the Cage Lock button on the rear mech, which makes for easier wheel mounting and removal compared to Shimano derailleurs. On rough trails, the derailleur's one-way roller bearing clutch puts good tension on the chain, reducing the chance of slapping and derailment.
However, the GX AXS derailleur itself is rather bulky compared to Shimano's equivalent derailleur. This is especially noticeable when you're using the smallest 10T cogs, where the outer knuckles of the derailleur are about 48mm outside of the hanger. While this does increase the chances of it clipping rocks from the start, the AXS design features a built-in overload clutch, which means the derailleur will move inwards in the event of a hit. This clutch helps protect the internal motor mechanism, and when (hopefully) disengaged, the derailleur will move back to its original position. Smart stuff!
It's also worth noting that our GX AXS shifters were equipped with regular paddles, not the new generation rocker paddles. Having used both, I prefer the classic paddles, with concave surfaces that provide a smooth platform for your thumb to flick up or down to command a shift. Riders looking for a more tactile shift feel and more defined upshift and downshift lever positions may prefer the rocker, though. The service will continue to be available as an optional upgrade for $35.
You can utilize the AXS smartphone app to change the shift mapping, depending on what feels more natural to you. The app also provides firmware updates for AXS components and gives you battery charge status.
Speaking of which, of course you need to remember to charge your AXS battery from time to time. SRAM estimates about 20 hours of ride time between charges. Unfortunately, you can't charge it with a standard Micro-USB cable like other devices - you have to use the special AXS battery charger that comes with the upgrade kit. If you're going on a multi-day cycling trip, don't forget to bring your charger. It might also be a good idea to keep yourself a spare battery.
Flow's early verdict
Given the commercial success of its wireless road and mountain bike groupsets, bringing AXS technology down to the GX Eagle level was an obvious move for SRAM. I've been driving the new GX AXS drivetrain for the past few weeks and I can say that the move has been executed very well.
Shifting performance is easy and stable, and while the derailleur is noticeably heavier than its more expensive counterparts, the fact that it's half the price makes the weight an easy trade-off for most trail riders. While long-term durability has yet to be determined, I haven't had any issues so far, and the existing XX1/X01 AXS kits set a positive precedent in this regard.
Of course, the GX AXS still isn't for everyone. There's another battery to remember to charge, and the shifting performance of the cassette isn't many light-years better than a well-tuned mechanical setup. While it's cheaper than the X01/XX1 AXS, it's still more expensive than most mechanical drivetrains - we're talking a $558 trans here.
The shifting action is much lighter at the thumb, though, and this becomes more apparent the longer you ride. Along with easy setup, a cleaner cockpit, and consistent performance from a cable-free design, the SRAM GX AXS offers a new, more accessible invitation to the wireless shifting world.