Installation and Setup
OneUp Components have quickly gained a reputation as a company that offers gearing solutions that simply make sense for the masses. They first debuted their 40 and 42 tooth cogs that allow ten-speed riders to take advantage of a wide-range, single-ring setup that they would have otherwise only been able to use by replacing their entire drivetrain, and the company has since come out with everything from narrow / wide chain rings, a downhill-specific cassette spacer/spoke guard, and even replacement cages for Shimano derailleurs. With the 44 tooth X-Cog, they're now offering a solution to those riders who could benefit from an even wider gearing range than SRAM's stock 10 - 42 tooth X-Dome cassettes offer, not just an easier low-end gear.
The 100 gram X-Cog is available in black or green, and is only compatible with SRAM's XX1 (XG-1199
) or X01 (XG-1195
) eleven-speed cassettes. It retails for $90.00 USD. OneUp has no plans to offer replacement 42 tooth cogs for those who wear out the easiest gear on their X-Dome cassette. www.oneupcomponents.com
Installing the X-Cog means prying apart your rather pricey SRAM X-Dome cassette with a big flat blade screwdriver, which is something that some riders may find unnerving. It's not that it's a hard thing to do, just that some could find it intimidating. OneUp equates the task to cutting a fork steerer tube down, and I'd have to agree - it doesn't take any special skills, but you best not muck it up. They also say that you're better off letting a shop mechanic do the job for you if you don't feel up to it, and I'd have to agree with that. You'll need a large flat blade screwdriver, a hammer, and the tools to adjust your derailleur's limit and B-tension screws.
The first step is to remove the X-Dome cassette from your wheel and place flat on a table. Slide your big flat blade screw driver between the stock 42 tooth cog and the 36 tooth next to it, making sure to align the tool with one of the eighteen press-fit pins that join the two. Twisting the screwdriver to the left or right slightly will begin to separate the cogs, but make sure to only go for a tiny amount at each joint rather than working to completely pry the cog off at each pin, and also try to put pressure onto the base of the cassette body rather than the teeth themselves. Working your way around slowly should see the 42 tooth cog pop off without any issues.
It may not look like it at first glance, but one of the eighteen press-fit pins on the back of the 36 tooth cog is actually slightly larger than the others, and OneUp says that on most X-Dome cassettes this larger pin sports a small groove to make spotting it easier. You'll need to find this pin and align it with the slightly larger hole (identified by a laser-etched arrow
) on the X-Cog before you join the two. Here's where it gets slightly violent: place the cassette face up with the X-Cog's press-fit holes lined up with the pins on the back of the 36 tooth cog, then align a flat blade screwdriver on the 36 and directly over the first pin before giving it a gentle tap with a hammer. Work your way around the cassette, tapping each of the eighteen pins into their corresponding holes. Again, you aren't trying to do this all in one go, so take your time and go around the 36 tooth cog three or four times.
The last thing to do before reinstalling the cassette on your bike is to make sure that the X-Cog is completely seated. Do this by getting down so that the cassette is at eye level, and then spin it slowly to make sure that the gap between the 36 and 44 tooth cogs is consistent all the way around. You'll likely also have to add a link or two to your chain, and OneUp says that the standard big-to-big (bypassing the derailleur
) plus four links will do it, but I'd check that length at full-travel by deflating your shock (write down your shock pressure first
) and bottoming the bike. You'll also need to tweak the low-limit screw, as the X-Cog does sit in a slightly different position than the stock 42 tooth SRAM cog, as well as turn the B-tension screw in at least one turn to move the derailleur's upper pulley wheel away from the cassette.
Double check your shifting and low-limit, then you should be good to go. The job took me about fifteen minutes, including taking the time to clean the cassette once I had the stock cog pried off the back of it.
As you might assume, SRAM is not a real big fan of any sort of modifications to their products, and this is especially true when it comes to the high-end X-Dome cassette. I reached out to SRAM's MTB PR and Media Coordinator, Duncan Riffle, to get his thoughts on OneUp's X-Cog, and he wasn't shy about bringing up industry standards and regulations, as well as the voiding of any and all warranties. ''Suggesting or endorsing a modification to our parts without proper testing isn’t a good idea. Furthermore, it voids ANY warranty we may provide,
'' he explained when I questioned him on modifying their X-Dome cassette. ''Also, it should be noted that making changes to the cassette is not just a cassette issue by itself, it is now using the chain and derailleur in a manner it was not designed or intended to be used. That’s also unwise and not recommended.
'' So there you have it: install the X-Cog if you like, but SRAM would obviously prefer that you don't.
I think that SRAM's concerns are valid given that the X-Dome cassette is an impressively machined piece of steel and aluminum that's all about precision, but I also also vaguely remember SRAM talking about offering replacement large cogs when XX1 was first debuted a few years back. That obviously never happened, but at the time, I took it upon myself to pry off a handful of 42 tooth cogs just to see, and I had no troubles re-installing them. That said, it clearly wasn't recommended, and the X-Cog isn't a SRAM product. It's also worth noting that SRAM's X-Horizon derailleur easily clears the 44 tooth X-Cog with room to spare, which has me wondering how seriously SRAM considered going even bigger than the X-Dome's stock 42 tooth cog, or if that clearance is there for some wiggle room when it comes to all the different bike designs on the market.
Shifting up to and down off of the X-Cog was surprising, but not in the way you might think. I expected the shift from the 36 tooth up to the 44 tooth X-Cog to be noticeably slower compared to going up to the stock 42 tooth cog, but that wasn't the case. I'd say that things were about equal when talking about just normal riding, but it was marginally slower to shift up to the X-Cog under heavy pedalling loads as you might find when halfway up a steep wall of a climb. I know, you're not supposed to shift when you're putting the ponies down, but you sometimes don't have a choice. Either way, the difference isn't enough to dock OneUp any points on this front.
However, shifting down off the cog was strangely slow, and it's something that no amount of tinkering with cable tension or the B-tension screw was able to remedy - the chain just wasn't eager to drop down from the 44 to the 36 tooth cog. Keep in mind that this was with a brand new shift cable and fresh housing, as well as a perfectly straight derailleur hanger. The shift does happen, of course, but it takes noticeably longer than with the stock 42 tooth cog. I'd argue that being able to shift into the easiest gear quickly as needed is more important than going the opposite direction and into a harder gear, but it'd be nice if it was quick going both directions. On this front, the X-Cog is not as good as the stock SRAM cog when talking about shift quality.
And just how useful did I find the X-Cog on the trail? Well, there's a chance that I might be in the minority here, but I'm not a believer in simply having as easy gearing as possible. If that was the case, I'd have a three-ring crankset on my bike, but I don't. I have a single-ring crankset, and I unashamedly admit to putting an emphasis on fitness and climbing strength because I believe that it makes one a better all around rider. I had been running a 30 tooth chain ring with the 10 - 42 X-Dome cassette and found my gearing to be pretty spot-on for the steep climbs in my 'hood, and I'd bounce around the cassette's three largest cogs depending on how I was feeling and what I was trying to get done. Putting the X-Cog on kinda messed that up a bit because now I actually found that my drivetrain's easiest gear was a bit too low for my liking, even for when I was looking for an easy recovery lap, but dropping down onto the 36 tooth cog (the next easiest gear
) made things a bit too tough when I was just looking to cruise. For me and how I ride, the step between the OneUp 44 tooth cog and the stock 36 tooth cog just didn't feel as natural as it did with the stock 42 tooth pie plate on the X-Dome cassette.
The obvious thing to do would be to change the size of the chain ring so as to get the most out of the new, wider gearing range that the X-Cog provides, and bumping up a few teeth to a 32 tooth 'ring would make a lot of sense for me. Yes, the jump between the 36 and 44 tooth cogs would still feel a touch odd, but I would then have the easy gearing that feels close to just right for me while also benefitting from a wider range. With this in mind, OneUp is also debuting their new $65 USD SDM (SRAM Direct Mount
) chain rings in 28, 30, 32, and 34 tooth sizes.
While the jump between the 36 and 44 tooth cogs doesn't feel ideal, the step down in gearing let me get up some short, steep climbs that I usually can't clean until I come into some 'summer fitness'. The X-Cog gives riders that ultra-low gear that some could take advantage of, but without the penalty of losing top-end speed that you'd pay by going with a smaller chain ring. It widens your gearing spread a noticeable amount, which, for many riders, especially those on heavier all-mountain machines, will be exactly what the doctor ordered. The other way to look at it is that it's there when you need it, but you obviously don't have to use it. Think of the X-Cog as a kind of 'bail out gear', which, as anyone who's wished they had such a thing during a big day on the bike, can really come in handy. It's also a viable product for riders who's cranks don't feature a removable spider, thereby preventing them from running a 28 tooth chain ring.
There's really two kinds of mountain bikers in my mind: those who want to get to the top and may care at least a little bit (or a lot
) about how long it takes them, and those who simply just want to get up there, period. The X-Cog is definitely for the latter. Pinkbike's Take:
|I do still believe that a stock SRAM 1x drivetrain will, so long as you choose your chain ring size correctly, offer pretty much any rider a wide enough range and low enough easy gear, but the X-Cog is that reasonably priced bit of insurance that basically keeps you from ever having to walk up anything that's remotely rideable. In effect, it takes your horsepower out of the equation, widens your entire gear range, and will let you climb up anything that your skillset will let you scale. - Mike Levy|
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