First Look: SRAM NX Drivetrain
The term "revolutionize" gets thrown around a lot in the ever-changing landscape of mountain bike technology, but it truly applies to what SRAM did with the drivetrain just a few short years ago with the introduction of its XX1 group. It was designed around an unheard of 10-42-tooth 11-speed cassette–enough range that only a single chainring would be needed. On top of that, the chainring required no guide whatsoever to prevent the chain from coming off. In one fell swoop, SRAM made the bike quieter, simpler, and more trouble-free. Now, with several years in the rearview mirror, the impact one-by drivetrains have had on mountain bikes is undeniably profound.
The biggest complaint hasn't been about the reduced gear range compared to double or triple ring drivetrains–most converts seem just fine with that part–it's the affordability. An XX1 cassette–just the cassette–retails for $415. Even the most recently released GX 10-42 cassette costs $144. Well, SRAM has been listening, and today the Chicago-based component giant announced the addition of its fifth and most affordable single ring group, called NX. Complete groupset pricing starts at $310–a full Benjamin less than just an XX1 cluster. How's that for trickle-down?
I keep talking about the cassette because if there's one major standout to the NX group, that's it. To dramatically cut costs, a decision was made to build the NX cassette using a standard Shimano freehub body interface rather than SRAM's XD driver interface used on its other 1x11 offerings. This results in a retail price of 80 bucks. It also means that the NX cassette's small cog has 11 teeth instead of 10. The reduction in gear range is the biggest practical difference between NX and GX–on paper anyway.
Here's a rundown of each component in the NX group, all of which are slated to be available starting in April:
1x X-Sync Crankset
If the crank looks familiar, that's because it's a rebranded GX-1000 crank with a slightly different finish. The fixed 94-mil BCD spider is compatible with rings down to 28 teeth. There will be another NX-branded crank sold to bike manufacturers as OEM-only, with the same 6000-series aluminum arms and a removable spider to allow direct mount compatibility. We'd love to see aftermarket availability on a crank like that. The numbers:
- Crank Arm Length:155mm, 165mm, 170mm, 175mm
- BCD: 94 or Direct Mount (OEM-only)
- Chainline: 49, 52, 66.5mm
- BB Compatibility:BB30/PF30-68/73mm, GXP 100mm/ PF GXP 121mm, GXP PF GXP 68/ 73mm
- Chainring Compatibility:28t, 30t, 32t, 34t, 36t, 38t, 40t
- Weight: 680 - 780g
- MSRP: $116
1x11 X-Horizon Rear Derailleur
The main change from the GX derailleur is the use of stamped steel instead of aluminum on the cage and inner link of the parallelogram. The clutch bearing, b-knuckle, and outer link are the same.
- 11-speed X-Horizon design
- 12-tooth X-Sync pulley wheels
- Compatible with all SRAM 1x drivetrains
- Steel pulley bearings and cage
- Weight: 322g
- MSRP: $74
11-Speed Trigger Shifter
All SRAM's other 1x11 shifters have Matchmaker mounts, allowing them to be mounted either to a fixed clamp, or directly to a SRAM brake lever clamp. NX is a fixed clamp. On the upside, a cable port allows tool-free cable swaps.
- X-Actuation 11-speed shifting
- Weight: 142g
- MSRP: $27
- Grip Shift option also available for $33
PC-1110 Chain
According to SRAM, the only difference between this new 1110 chain and the rest of its 11-speed X-Sync offerings (with the exception of the XX1 chain) is finish quality. Typically this is more about corrosion resistance than strength or shift quality. With proper care, a basic chain can last just as long as something with a higher finish quality.
- Optimized for X-Sync rings
- 11-speed compatible'
- PowerLock Connector
- Solid pins
- Chrome hardened treatment
- Weight: 232 - 273g
- MSRP: $14
PG-1130 Cassette
As stated earlier, the cassette is Shimano driver only, dictating a smallest possible cog of 11 teeth. The largest three gears are attached in one cluster while the remaining 8 are individual cogs. We'd recommend mounting to a steel driver body because cassettes with this many individual cogs tend to gouge alloy bodies.
- Compatible with non-XD (Shimano) driver body
- 11 speed, 11-42t gearing
- Cog sizes: 11t, 13t, 15t, 17t, 19t, 22t, 25t, 28t, 32t, 36t, 42t
- Cogs on cluster: 3
- Weight: 538g
- MSRP: $79