SRAM have taken a step back to 7–speed with their new DH drivetrain, but it’s the future.
DIRT ISSUE 146 – APRIL 2014
Words by Ed H. Photos by Ed H
For years SRAM have resisted making a dedicated DH drivetrain, but recently I was lucky enough to get to test out X01 DH, which is exactly that, and boy was it worth the wait. Amidst the ever–increasing number of cogs on a rear cassette, DH riders the world over have been crying out for something less, and that’s exactly what SRAM have now delivered. This is most definitely a case of less is more.
So yes, this new X01 DH drivetrain is 7–speed, but there’s more to it that just fewer gears. As you might have guessed from the name SRAM have taken everything that they’ve learnt from developing XX1 and X01 (there 1 x 11 speed groupset), and then tailored it for DH use. Most people tend to think of the main advantage of XX1 being the narrow/wide chainring, and yes X01 DH does include that too, but I think the performance of the unique rear mech is all too often overlooked. I shan’t bore you with all the technical details about why it is so good, because all you really need to know is that it produces the kind of shifting that you’ve previously only dreamt of. Crisp, precise, reliable, silent… it really is incredibly impressive, especially when you use it in harsh terrain. It doesn’t matter how hard you hammer on one of these mechs, you never get any ghost shifting or inconsistencies, it’s definitely a significant step up when compared to a regular rear mech.
Now I will talk about the 7–speed cassette in a moment, because it is definitely a significant part, but before I do that I just want to mention the fact that SRAM have announced they will also be offering a 10–speed version of the X01 DH rear mech. This is big news in my eyes because whilst the 7–speed version is what many of us have dreamt of, you are going to need pretty deep pockets to be able to take advantage of it. On the other hand, if you’re currently running a 10–speed SRAM setup on your DH bike then you can benefit from a significant proportion of what the new drivetrain offers by simply buying this new rear mech. I take my hat off to SRAM for providing this cheaper option from day one.
Anyway, let’s now get onto the 7–speed aspect… SRAM are only going to be offering one 7–speed cassette ratio, but that’s definitely not a problem because it’s the ratio that SRAM have come up with that helps to make X01 DH so good. The 10–24 cassette (which runs on an XD driver body) offers all the range you’ll ever need for a DH bike, and perhaps even more importantly the gaps between the gears are spot on. When I first started testing it out I found myself over–shifting and then having to shift back, but that’s because my brain is obviously subconsciously used to a close ratio road cassette where I often need to skip gears to get where I want to be. With this new cassette though one shift is almost always all you need, and less shifting means more time to get on the power. SRAM have also found that the slightly larger jumps are kinder to a chain when shifting than the one tooth jumps on a road cassette.
So, the rear mech and cassette are great, and so for that matter are the cranks and shifter, but is there anything I didn’t like about X01 DH? Well yes, and that’s that I really wish SRAM had found the balls to release a new shorter driver body too. Normally I hate new standards, but it seems a bit perverse to me to create the room to move spoke flanges further apart (which makes your wheel much stronger), and then not do it. Who knows, maybe that’ll happen in the future, but in the meantime this is definitely the best drivetrain that I’ve ever used on a DH bike.