e*thirteen had a plethora of prototypes on hand, only showing off things that are at least a few months out. The most interesting was this prototype EXF Cassette, which will offer a wide range set of cogs that runs from a 9-tooth up to 42-tooth in both 10 and 11 speed options. Following that will be an 8-speed version for DH, but that one’s still in testing with the Polygon/UR Team.

Weights should be in between XX1 and XTR, but it should come in much cheaper. Final MSRP is TBD. The lower cluster is steel, made in two pieces that are bolted together.

The upper 3-tooth cluster is aluminum and slides onto the freehub body portion of an XD Driver with a lock ring that holds that piece in place to attach the cassette to the wheel. Then the lower cluster slots into the upper section and a chain whip is used to twist and lock it into place. Wanna see the back side?


Hooked flanges on the lower cluster slot into the grooves on the big one, then are twisted into the grooves to lock it into place. They’ve been working on it for quite a while and are continuing the mechanical and real-world testing to ensure it remains solidly together.

Final production colors are likely to change.

UPDATE: at e*thirteen’s request, some of the internal photos were removed due to IP concerns.


The threads that a normal XX1 cassette screw onto are at the back of the XD Driver body, and e*thirteen uses those to place a lock ring up against the upper three cogs. Then add on the little piece and it all adds up to a massive 467% range.

They did mention that this isn’t meant for road applications where you might be spinning the 9-tooth at high speeds because the chain can want to lift off. But for mountain biking, the speed isn’t high enough to cause issues. And, let’s face it, we don’t spend much time in the smallest cog anyway.


The LG1r and TRSr Trail are their first carbon cranks, and both use the same arm with different spindles to suit the intended use their model names imply. The LG1r has a 83mm spindle for DH bikes and the TRS has a 73mm spindle for standard mountain bikes, which will work with 68mm frames by adding spacers.


Weight should be between a Race Face Next SL and SixC, but tough enough for DH use. The spindle and outside facing bolts will all be black, too.

They get a new alloy APS preload knob, which pushes the center section out to take up any slack while remaining fully sealed to keep mud out from between it and the crankarms.


The direct mount narrow wide chainrings are a new forged, machined piece that will replace the current Guidering M. Still in testing on all of this stuff, both on the trail and in machine testing, so they’re looking at late fall on the cranks and cassette.


The carbon arms are very thick, suggesting massive stiffness.


The upcoming LG1r chain guide will get a carbon backplate option that’ll save a bit of weight. Actual weight and pricing is TBD.


The ISCG shims will come with all chain guides starting in June. They come in 1mm and 2mm and replace all the litte random washers some folks are using to space the guides away from the frame.



  1. Chai guide?! About time! On a serious note, those ISCG spacers are genius.
    editor: Yeah, we have a hard time choosing the proper tea blends. Oh, but this was meant to be chain. Sorry.

  2. “Lick ring”? That conjures up a whole load of mental images I don’t want to see…
    editor: Come on, who doesn’t want to lick a cassette to hold it on. Oh, oops again. That should have been a lock ring.

  3. “They did mention that this isn’t meant for road applications where you might be spinning the 9-tooth at high speeds because the chain can want to lift off.”

    Interesting, never heard about this before. It should also affect Shimano’s 9t Capreo cassettes then, especially since they’re intended for small wheels, which spin faster for a given road speed. Never heard about that happening, but could be possible.

  4. The big news here is those spacers. Not sure why it took this long to realize washers wasn’t the right way to do that.
    Curious on price of those cranks as well.

  5. Most important question, will those ISCG shims be available after market, because there’s a collection of random washers on both my bikes that I am just itching to throw away.

  6. There was an article a while back where Sram mentioned that they tried a 9T version of the XX1 cassette, but said they didn’t use it because the chordal effects got pretty bad and riders didn’t like it. I’ve never tried the capreo stuff – but I’d be curious to hear what experience those folks have had with that cassette.

  7. This isn’t an issue for Capreo bikes because those hubs are used exclusively on folders with tiny tires. The huge chainring and tiny cog are necessary to get a remotely high gear ratio. Ground speed is far lower, and chain speed is also lower.

  8. @Eric You sure? The way I read things, ground speed doesn’t matter for chordal action. All that matters is size of cog (small is bad) and cog/hub rotation speed (fast is bad). My math says a small 406/20″ wheeled bike doing 21 km/h (or mph, units don’t matter) has the same hub rotation speed as a roadbike doing 30. Small bike doing 30 equals roadbike doing 43.

    I’ve done 44 km/h on my 2-speed folder (=63 km/t roadbike). And there are much faster folders out there: http://www.ternbicycles.com/sg/bikes/verge-x30h

    So yes, if you put Capreo on one of those it seems it could be a real problem.

  9. Big rings are better.

    I totally agree with Ring about a 9 or 10t cog being a bad idea.

    Chordal action, articulation angle, tangential motion, all good terms to know.

    For a light primer check out Spicer et al. 2001
    “Effects of Frictional Loss on Bicycle Chain Drive Efficiency”

  10. I’m thinking if you need a 10 or 11 tooth cog for downhills you probably weren’t pushing hard enough going up the hill. 😉

  11. @Gunnstein I couldn’t find a reference, but chain speed can differ even at the same gear ratio. There was an article very recently on infinitesimal drag caused by chainring size selection, and optimal points to shift chainrings with respect to chain drag. They had formulas to model all this. I’d like to apply that to the huge chain rings on a folder.

    I’m not saying “9 toothed cogs are fine”, e.13 says there not in this application. They appear to be fine in other applications, so math needs to be done.

  12. @Eric Aha, wasn’t sure what you meant by “chain speed” at first, but I see it now. Yes, there is a small efficiency gain by always using the largest possible chainring and cog for your wanted gear ratio, but you have to optimise for chainline too, so it’s complex.

    I’m not saying 9t cogs are bad, either 🙂 I guess I’m saying that IF they are bad on road bikes, then they are ALSO bad on small wheel folders that are ridden fast, even if they are not ridden as fast as the road bikes. (The factor to compare speeds is about 0.7)

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