Having spent 10 months hammering one of our long-term test bikes with X01 we’re yet to find the weak point in SRAM's groupset. Minimal TLC and thousands of miles across Alpine and UK mud haven’t bought it to its knees, yet.
The 10-42T cassette – as wide as it gets for a 1x setup – is machined from a block of 4130 steel, taking three hours to create. The process is barely any different from how the 15g lighter XX1 item is made, hence the similarity in price. A more obvious difference is that XX1 uses a super shiny nickel finish while X01 gets a black anodized coating.
The cassette shifts impeccably, even when powering out of the saddle, largely thanks to the shifting ramps that pepper the teeth. During testing, some of the coating’s worn away, but the teeth are still in good shape, with no noticeable shark-toothing and continued excellent shifting in virtually all conditions.
Multiple shifting ramps provide silky changes – which remained constant after months of hard labour
The X-Horizon rear derailleur only moves horizontally, reducing vertical movement for smoother shifts. So far it’s shown no sign of wear in the pivots. Being single ring specific means the derailleur doesn’t have to handle so much chain growth, and its horizontal movement makes pulling the chain onto the large 42 sprocket smooth.
The Matchmaker compatible shifter lacks the multiple upshift function of Shimano kit, but the thumb paddle is handily placed for quick changes and there’s no lag in the downshift lever, making shifting crisp and instant.
X01 cranks come with a 94mm BCD, meaning the smallest ring you can use is a 30T rather than the 28T lowest option for XX1. While running a 32T ring we’ve rarely found the range of gears on offer from the 10-42T cassette a problem, and the X-Sync thick/thin tooth design hasn’t dropped a chain yet, despite our best efforts.
Aftermarket groupsets come with a carbon crank, while bikes with X01 fitted from the factory will likely come with an alloy version, the same material differences applying to the mech cage. Our arms lost a fair bit of their black coating during use though.
One of the big questions over 11-speed groupsets is the longevity of the chains, but ours has only stretched slightly over 10 months use. One test chain has snapped, but that took two grown men pushing hard on a tandem.
All in all, the simplicity and effectiveness of the system won us over. With rings from 30 to 38 teeth, there’s a range to suit most.
That said, the complete X01 groupset with GXP bottom bracket option comes in at just £142 / US$240 / AU$550 less than XX1 and only weighs a touch more, which does make choosing between the two tricky.
This article was originally published in What Mountain Bike magazine.