Good reasons to drop £495 on a new groupset? There are some tech advances: new cassette has an extra tooth, taking it to 10-52t and a 520% gear range!

>>> Shimano XT M8100 groupset review

SRAM Eagle GX Pricing

• Shifter £36
• Rear Derailleur £110
• Cranks £134
• Cassette £196
• Groupset (mech, shifter crankset and chainring, chain and cassette) £495

SRAM’s GX Eagle has always been a pretty high-end groupset, but it’s never exactly looked the part. SRAM has worked hard to make it look slicker for this latest release, now coloured “Lunar” (silver, to you and me), with four chain colours (black, gold, rainbow or copper) to tie it all in to your bike.

SRAM plays a continual game of one-upmanship with its great rival Shimano, and it looks like once again SRAM is a few inches ahead with GX. Just last month Shimano proudly dropped its new Deore M6100 drivetrain, a 12speed system with a 51t cassette. Perhaps it’s no surprise to see SRAM adding just one more tooth to its bite then.

You don’t need to buy an entire new drivetrain to get the extended range either – a new cassette will work just fine. SRAM says you need the new mech to make it work optimally, but it’ll work with your old 12 speed derailleur, we think.

You also don’t need to get a new driver body for your rear wheel, it mounts onto SRAM’s regular XD driver. This last part is really important, because while 12 speed Shimano demands a whole new Micro Spline driver body, with SRAM you can just slide the new cassette onto your old wheel. The tech improvements don’t stop there either, you can get a carbon version of the crankset, or stick with aluminium.

Cassette

SRAM told us the new GX Eagle cassette is an incredible piece of engineering… they would say that though. But it really is an intricate piece of design, where the steel cogs are fixed together with tiny steel pins. This means it’s still not as expensive as the intensively machined X-DOME cassettes higher in the range, but it now offers most of the advantages – chiefly, lower weight and better mud clearance.

Rear derailleur

SRAM has adding one more tooth to the biggest sprocket on the cassette, but left the gear ratios untouched. This creates quite a jump between the two biggest sprockets, and necessities a new rear mech for optimal shifting, SRAM says. Will your old 12 speed mech work? Probably, but it won’t be as crisp, reliable or durable. SRAM says is “updated cage architecture and the cage’s structural integrity” – that means they’ve changed the pulley wheel offset and lengthened the parallelogram.

Carbon GX Eagle crankset

This is the first time SRAM has introduced a carbon crankset to GX level, to offer more choice for bike companies and riders looking to upgrade. It comes with SRAM’s X-SYNC 2 tooth profile direct mount chainring, uses a proprietary carbon layup technology and is fully compatible with any 1x drivetrain. The crankset uses SRAM DUB technology for the bottom bracket fitment, better sealing against contamination and is forward and backward compatible.

You can still get the GX Eagle DUB Crankset in aluminum of course, and SRAM says this is the best aluminum crankset it makes. There’s not much change here though, it’s still DUB, direct mount and using the X-SYNC 2 tooth profile. It does come in the new Lunar colour though.

GX Eagle Trigger Shifter

No change here either, besides the colours. The trigger is made from aluminum and it’s MatchMaker X compatible. You can also get a Single Click version for e-bikes, which is designed to protect your rear mech from being mangled by an electric motor.

Anything else?

There’s a new chain gap tool to help you set up your rear mech. The really good news is it’s now universal and will work across all of SRAM’s drivetrains.

SRAM GX Eagle First impressions

By Mick Kirkman

I’ll admit to a bit of cynicism when I first clocked the latest GX Eagle’s massive cassette. Perfectly happy with the latest SRAM 10-50t drivetrains, why did I need a potentially heavier and worse-shifting 52-tooth cassette?

When fitting it, it turns out the cassette (that’s now even more ‘American’ than ‘European’ dinner plate-sized) is only part of the story. The finish and profiling of every part is really refined and sleeker than before, and I also switched to shorter 165mm cranks to get more ground clearance on a Specialized Enduro that has huge amounts of rear travel.

Lockdown has forced me to test kit exclusively on home trails. Not having the option to go elsewhere, has meant only riding trails I know like the back of my hand, so everywhere I’ve ridden GX Eagle, I’ve ridden countless times before on various bikes and drivetrains. And knowing every little bump in the trails and every point to shift gear or put extra effort in on climbs tells you a lot.

The main realisation on one super steep climb I lap regularly was how suddenly it was way (way) easier with the extra bail out gear to keep spinning smoothly and save energy. I wasn’t having to get out of the saddle to crest a couple of the steepest lumps and risk wheel spinning, and the easier gearing was different enough to changed my perception of a climb done hundreds of times; I could basically summit without overheating or having to push a couple of little pitches if I wasn’t on my A-game like previously.

The weather’s been glorious, so the drivetrain hasn’t endured heavy mud or constant wet, but it’s been plastered with bone dry dust and grit to the point it’s constantly thirsty for lube. And throughout dozens of rides it’s stayed quiet and performed flawlessly. The shifting hasn’t skipped a beat and feels even more precise and snappy than the previous generation GX, which might be down to the stiffer AXS-style cage on the rear mech (or, admittedly, a different bike and the fact it’s brand new).

I love how the stubbier cranks never feel like they’ll strike the ground and also spin smoother circles to take advantage of lower gear ratio. There’s a fraction more lag as the chain jumps up from the 42t cog to the biggest 52t, but it’s a pretty smooth transition, and feels quicker on the way back down, especially if you dump a chunk of gears at once.

First impressions of the new GX are excellent so far then, and I’ll keep on riding and report back when the drivetrain’s had more hammer in all conditions at the end of the summer.