SRAM XX Drivetrain review

Flagship mountain bike transmission

GBP £1,351.94 RRP | USD $2,430.00

Our review

An expensive but terrifically well-built evolution of drivetrain science
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SRAM’s flagship XX groupset was launched in 2009 amid much excitement. But when the uber-components hit the shelves, people were aghast at the huge price tag. We wanted to see if the heart of this component set, the 20-speed drivetrain, was worthy of the hype.


We specced our test rig with a 28/42 chain ring combo up front and an 11-36 sprocket range at the rear. This gave the same spread of gears as a22/32/42 chainset and an 11-28 cassette, but with one less chain ring.

Clever placement of the shift pick-ups and release points mean that big jump from 28- to 42-tooth chainrings is super smooth. Full power up-shifts do ask too much of it, but then how often do you up-shift across chainrings, while giving it full gas?

The rear shifting feels exactly like nine-speed SRAM X.0 – accurate and instant – but can be a little clunky, particularly on up-shifts.

Riding 2×10 takes a little getting used to, but the result is far superior performance, compared to a triple chainset. As we crested climbs we found that we could stay in the smaller chainring and just click our way down the cassette as we picked up speed.

All ten sprockets really are usable in both chainrings without compromising chain line, meaning we used the front mech far less than we would with a triple chainset.

Most of the time we stayed in the larger chainring and used the full range of rear gears. This helps keep the chain on when battering through the rough, and reduces wear, because more teeth are in contact with the chain.

So what do you get for your money? Well, the cassette is a work of CNC art, with eight of the sprockets machined from a single billet of steel, and then bolted to the largest aluminium sprocket.

The cranks have carbon arms and spin on ceramic bearings. The rear mech sports titanium hardware, magnesium inner link, carbon cage and ceramic jockey wheels, and the shifters have a carbon fibre lower lever. So you do get a lot, but for an awful lot of money.

This is out of reach for nearly everyone, but it’s the birth of new technology and we’re already hearing that 2×10 will be available in SRAM’s X.0, X.9 and X.7 levels for2011. We really cannot fault the concept or the execution of XX, and salute SRAM for bringing something new to the table.


That said, we would recommend waiting till more realistically priced versions of this awesome technology are available before buying in.

Product Specifications


Name XX Drivetrain (10)
Brand SRAM

Description System weight: 945g, rear mech 181g, front mech 118g, shifters 183g, cassette 208g, chain 255g, Options: Front mech: Low or high clamp, direct mount, top or bottom pull; cassette: 11-36, 11-32