When the Eagle groupset was launched everyone was shocked by the big 50T cog. The jokes kept on coming and they were pretty creative, mostly containing terms like pizza (referring to the big cog) or gold (referring to the chain color). Even we had a picture taken with the cassette covering my entire face. Anyways, from the first test, we embraced the idea of not using a front derailleur anymore, even if we are die hard fans of the 2×11 gearing.
The GX came as a necessity to offer an accessible product, the top model being dedicated to riders with a deep pocket or professional athletes. Lately Sram announced the new NX Eagle model, being even cheaper but heavier. Coming back to GX, I can say I would rather choose it over X01 because the weight difference is small but the price difference is big and this makes GX the most attractive version out of all that are available. An advantage of NX over GX is that it can be mounted on a regular hub, it does not require an XD compatible hub. In the case of our test bike, with Mavic wheels, we found an XD compatible freehub that was easy to mount on the rear wheel. Take in consideration if you have Shimano wheels or Shimano freewheel on the rear wheel, you cannot instal an XD cassette, therefore you cannot use the Eagle groupset.
When you will buy this groupset, you will care about this numbers:
10t, 12t, 14t, 16t, 18t, 21t, 24t, 28t, 32t, 36t, 42t, 50t
They represent the number of teeth for each cog. GX gives you the option of mounting different sizes of chainrings: 30, 32, 34, 36 or 38, including oval versions. To get an idea, the 30T chainring is for beginners, offering a climbing ratio of 0.6 and a speed ratio of 3, while the 38T offers a climbing ratio of 0.76 and a speed ratio of 3.8. By comparison, a 2×10 gearing in a 11-42 and 26-36 format, offers a climbing ratio of 0.61 (so slightly heavier going up) and a speed ratio of 3.27, meaning a slightly slower speed when running on flat terrain as compared to the 38T chainring of the Eagle. To reach somewhat similar ratios, you can choose the 32T chainring for Eagle, which will mostly cover the ratios offered by a 2×10 system (excluding of course some in between gears). In the case of a 2×11 transmission, for a cassette of 11-46 and 24-34 chainrings, you cannot find something better for the climbs, because of it’s 0.52 ratio. Regarding maximum speed, the ratio of a 2×11 is 3.09, which is smaller compared to 1×12 or 2×10. Knowing all this info, you can check what works for you, specially whether you are a spinner or a grinder or if you ride many flats or difficult climbs. Anyway we look at it, GX gives you the right amount of gears and the right ratios and as a plus you will have only one shifter.
Regarding materials used, GX comes with aluminium crank arms, so you won’t feel sorry when you hit them against rocks, the rear derailleur looks pretty solid also and the shifter is safe on the handlebar. I cannot speak about the long term usage of the components, but we know from the 11x groupsets that chains and sometimes cassettes have a shorter lifetime, mainly because chains are more narrow and in the case of a 12x cassette there are some more “tense” positions (I am of course referring to the diagonal lines). The chain is stable, the groupset is not that noisy, and I must say I used a chainguide that was already on the frame. Even so, you should have no problems with dropped chains on the Eagle.
Otherwise, the system works well together, perfect and precise shifts, something we are already used to when it comes to Sram. The shifter is not 2-way release, so it will take some time getting used to, if you come from a Shimano groupset. On the track the gears were enough, but sometimes I felt the need for a 46T cog instead of the 42T one, but even so, I did most of my climbs on the 36T or 42T cog, only when things got really steep I went for the 50T. It’s worth mentioning that this depends a lot on the bike we used. For instance on our enduro bike with 170mm travel and 14kg heavy, we used the 50T more often, with a 30T chainring. While on our XC bike we used it less often and we combined it with a 32T chainring.
In conclusion, we believe that GX is the best alternative for what is currently on the market, because of its price, weight and gearing ratios. Everything is much more simpler, even if you are missing some intermediary gearing compared to 2x systems. If you are a hobby/amateur rider, you will probably not miss them. The groupset was great on both XC and Enduro bikes, especially for longer bike rides.
Weights and prices:
Crankset with 32T chainring: 633 gr
10-50 cassette: 452 gr
Shifter: 125 gr
Rear derailleur: 296 gr
Chain: 315 gr
XD freewheel for Mavic wheels: 67 gr
Total weight: 1.821 gr / 4.01 lbs (without XD freewheel) – 555 EUR RRP (but you can find it as low as 370 EUR)