Update: SRAM X01 DH Drivetrain

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I wrote my initial review of the X01 DH 7 speed drivetrain a little over a year ago. Since then, I’ve spent quite a bit more time on it and have come to some realizations.

My conclusion last year was that it’s the best performing DH drivetrain on the market, but it’s expensive, and it has some durability issues. To some extent, SRAM has addressed the price issue – they released the GX DH drivetrain, which is quite a bit cheaper than the X01.

But that leaves the durability issue. As I noted in my initial review, my problems were with the derailleur. I snapped the B-set plate after four days on the derailleur, and so far this summer I’ve gone through 4 of those plates. The longest I’ve gone without breaking the rear derailleur was four days.

Noah Bodman reviews the SRAM X01 DH 7 speed drivetrain for Blister Gear Review.
Noah Bodman on the SRAM X01 DH 7 speed drivetrain, Whistler, BC.

And to be clear, the derailleur never broke because I hit it on something. My chain wasn’t too short, and everything was adjusted properly. I even tried a stainless steel B-set plate from “The Fix” in Whistler (it lasted 2 days, and it took out my derailleur hanger when it broke).

Added to those issues is the fact that I have to dump biblical proportions of loctite on the derailleur hanger bolt to keep it from rattling out of my frame. With a “normal” amount of blue loctite on the bolt, I generally have to re-tighten the derailleur every other run.

Every other piece of the drivetrain has performed flawlessly, but in my opinion the derailleur is complete junk. From talking to a number of mechanics in Whistler, it’s pretty clear that this is common problem, so I set out in search of a solution.

After cross referencing some gear actuation ratio tables, I’ve found a solution: with minor modifications, a Shimano Saint derailleur works well as a replacement. I’m now running a SRAM X01 DH 7 speed shifter, cassette, and 11 speed chain with the Saint M820 derailleur. It shifts very nearly as well, and I don’t have any of the issues that I had with the X01 DH derailleur.

All that needs to be done to get this setup to work is to add a ~2 mm spacer under the cable pinch point. This slightly reduces the amount the derailleur moves on each shift, which works perfectly for mating it with the 7 speed shifter and cassette.

Noah Bodman SRAM X01 DH Update for Blister Gear Review
Spacer setup

Aside from resolving the durability and rattling loose issues, the Saint derailleur is also a bit slimmer, and tucks under the chainstay a little more cleanly. And if you don’t want to pay for a Saint derailleur, this modification will work with and Shimano 10 speed Dyna-sys derailleur.

Bottom Line

There’s a lot of upsides to the X01 DH drivetrain that I laid out in the initial review, but the durability issues were beyond frustrating. Incorporating the Shimano derailleur resolves that issue, and if you’re buying the drivetrain new, the Saint derailleur costs almost half as much as the X01.

4 comments on “Update: SRAM X01 DH Drivetrain”

  2. One question:

    Could you do the same thing with a Saint shifter/derailleur combo and the SRAM DH cassette/chain?

    I’ve been thinking of converting my bike to 7-speed, and already have saint shifter/der. The SRAM cassettes look awesome, but would rather not upgrade the entire drivetrain.

    Thanks!

    J

    • Hi Jerry,

      I think you could get it to work. The 7 speed Sram cassette is the same spacing as a Sram or Shimano 11 speed cassette – there’s 3.9 mm between each cog. Your Saint shifter and derailleur are built for 10 speed cassettes, which have a 3.95 mm spacing. So basically, on each shift, you need the derailleur to move .05 mm less per click.

      That’s a really small amount. If I have this correct in my brain (which is somewhat questionable), I think you’d just need a very thin spacer under the cable pinch point to reduce the leverage ratio of the derailleur slightly, so it moves .05 mm less per click. With a bit of experimenting, I think it’d work, but I’d be a little hesitant to drop the not insignificant amount of money on the sram cassette before knowing it’d work (not to mention you’d need an XD compatible hub).

      If you know anyone that has an 11 speed shimano cassette that you could borrow for a bit, throw that on. It has the same spacing between the cogs as the Sram 7 speed cluster. if you can get the system to shift well on the 11 speed cassette, it’ll work fine on the 7 speed.

      Happy tinkering!
      -Noah

  3. Same exact thing happened to me at whistler last year 2016!! I had 2 bikes with this(SRAM X01 7-speed)setup and they both failed 2 x each within 48 hrs. I was pretty frustrated and all the Whistler bike shops were sold out of that part and all said it was an epidemic that summer so their stock was completely wiped. I also went to “the Fix” shop and bought a few hardened steel collars (sick shop btw)thinking that would get me back in biz for sure…wrong! Neither lasted 1 lap down Dirt Merchant before they hand grenaded, chain came off and the derailleur was just slapping itself to death on the brake bumps. The SRAM design is flawed & just doesn’t hold up and it’s supposed to be a DH derailleur! C’mon neeow…Friggin joke! I went back to Shimano Saint and been rock solid ever since. The SRAM setup, while looks dope, light weight and 7-speed is desired for the kind of riding I do needs some more R&D especially at that price point for a pos component.

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