SRAM has expanded it's wide-range 12spd mountain bike drivetrains with a new, much more affordable NX Eagle option. Coming in at around £365 for a complete drivetrain, it's going to bring their gearing systems to a whole new and much more affordable price point.

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Much like it's more expensive brethren, the new, single ring only NX Eagle drivetrain gets 12 ratios, but there have been numerous tweaks to get the cost down to almost a third of a top end SRAM Eagle XX1 setup.

While it shares the whopping great 50T big sprocket on the cassette with the high-end Eagle groups, NX Eagle has an 11T small sprocket rather than the 10T item. While this drops a little bit of gear range, it means that you can use a conventional freehub driver body instead of the specific XD unit. As finding more affordable wheels with an XD driver is tricky, this opens up manufacturers to speccing the group of a far wider range of bikes.

Of course, this isn't the only way that costs have been kept down. Instead of having a cassette machined from a single piece of steel (a la X01 and XX1) or made from numerous sprockets pinned together, like GX Eagle, NX Eagle uses an alloy carrier for the four largest cogs and then eight conventionally produced smaller sprockets. SRAM claim it's tough enough to be used on e-MTBs - in fact, it's the only Eagle cassette that is. At a claimed 615g, it's a fair bit heavier than the 360g or so XX1 item, but you pays your money...

Elsewhere, it's a similar story, with cheaper methods and inevitably weightier methods of construction used in the chain, derailleur and shifter - though all are cross-compatible with any other part of the SRAM Eagle lineup. There's also an alloy armed chainset which comes in three lengths from 165mm to 175mm and it uses stamped steel direct mount rings with the fancy new X-Sync tooth profile. You can also get it in their new DUB bottom bracket format.

At £365 for an NX Eagle drivetrain with DUB bottom bracket, it's a fair bit more affordable than the previous cheapest 12spd group, which was GX Eagle at £495. As well as looking like very good value aftermarket, this group should also let SRAM tap into a much bigger market for complete bikes, an area Shimano has traditionally dominated. With the latter only just having announced a 12spd drivetrain in the form of XTR, it looks to be interesting times ahead in the drivetrain wars...

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