Between SRAM XX1 and X01 groups, direct mount cranksets, and extended range cogs, there are plenty of options to convert your bike to a 1BY mountain machine.
Last year, SRAM shook up the MTB component scene when XX1 hit the market. Rather than the latest-and-greatest drivetrain getting more complicated, they ditched the front derailleur all-together in favor of the simplicity of a single-ring setup. It was a revolutionary move and one that has since influenced all corners of mountain biking; from cross-country race, to all-mountain and enduro – even spilling over to freeride and downhill.
First, what’s 1BY?
1BY, or 1×10 and 1×11, refers to a single-ring drivetrain where only one chain ring is connected to your crank, and a 10- or 11-speed cassette in the rear of your bike. This differs from the traditional setup where you have 2- or 3-chainrings up front and a derailleur to change gears.
So what’s all the hype about?
1BY setups have been around for a while in the cross-country race scene, but few mortals were able to take advantage of the single front ring setup with a conventional 11-32 or 11-34 tooth cassette (and still pedal comfortably). When SRAM released XX1 the 1BY movement became a viable option for “average” riders.
But the 1BY story is about more than just a single ring front crank – it’s a system. By expanding the gear ratios in the rear cassette (10-42T), your everyday rider can now run a single ring up front and get the same gearing as a standard 10×2 or 9×3 setup.
Why make the move to 1BY?
Three main benefits: single-ring drivetrains are lighter weight, offer better ground clearance, and are more reliable than a traditional 2- or 3-ring setup.
A 1BY drivetrain means there’s no front derailleur to fiddle with, and that means fewer headaches on the trail and less maintenance overall. Shifting is simplified, and that’s something that riders of all abilities will appreciate; from novices just getting the hand of their gearing, to racers looking for reliable shifting when every second counts.
An added plus, no front shifter also means more real-estate on your bars for that dropper post lever, or suspension lockout. If you run a narrow wide front ring, in most cases you can also chuck your chain guide and forget about dropped chains.
Below are three options to convert your mountain bike to 1BY, starting with the smallest investment and moving onward and upward from there.
Option 1: Convert your existing cranks to 1BY (narrow-wide) and modify your 10 speed cassette
Kick your granny gear to the curb and swap out your middle ring for a Blackspire 30 tooth MonoVeloce Narrow Wide chainring for fewer dropped chains. Then install one of e13’s Extended Range (EX) cogs to expand your cassette to 40T or 42T. Remove your front derailleur, cable and shifter, and rejoice!
Option 1 estimated MSRP: $152 CAD.
Option 2: Replace your front crank to a dedicated 1BY crank and modify your 10 speed cassette.
There are a few new 1BY cranks hitting the market designed for optimal performance with large range rear cassettes. E13’s TRSr cranks feature a dedicated 1BY chainring with narrow wide tooth profiles, plus shed weight by going to a direct spiderless chainring interface.
Pair this crank with E13’s rear EX cog and your set to hit the mountain in style and performance.
Option 2 estimated MSRP: $569 CAD.
Option 3: Replace your complete 10-speed drivetrain over to SRAM XX1 or X01.
If you want the best-of-the-best, then converting your complete drivetrain over to 1BY is the way to go. Forget 1×10 setups, and crank it to 11 for the full experience.
Why 11-speed? Besides additional weight savings, the real answer is in the expanded gear range. Due to the interface of traditional 10 speed freewheels, you can only go down to an 11T cog. By converting your bike over to 11 speed (with a XD freehub body) your rear cassette can now start at a 10T, giving you the largest rear cassette on the market today (10-42T). By having a larger cluster in the back, you get more options when paired with a single front chainring.
But converting to 1×11 does have its costs. In order to convert, you need to purchase a dedicated crank, cassette, chain, derailleur, and shifter along with a new XD freehub body or rear wheel (if your current rear hub is not convertible to XD). On the bright side, you don’t need a front derailleur or front shifter.
SRAM offers two complete drivetrains for 1×11: XX1 and X01*. XX1 caters to the elite rider with optimal weight saving and stiffness, while the X01 option provides the same ride characteristics in a more affordable package.
Option 3 estimated MSRP: $1,500 – 2,000 CAD.
*Update: SRAM is currently in development of a new X1 platform which is targeted hit a lower price-point of $1000 MSRP CAD.