There is a trendy preference of 1x drivetrains over a now more traditional 2x setup in recent years. My first reaction to this was to ask a question is it a justified trend or did marketers just did their thing to sell us something new, and more expensive… again.
While doing my extensive research and testing I found that 1x drivetrains have advantages like easier gear changing, less weight, and it gives you more room for other essential bike upgrades on your handlebars. However, this comes at a price of increased wear of drivetrain components, unwanted gear changing, sometimes limited gear range, and chain drops on cheaper drivetrain chainrings.
You may not remember this but this isn’t the first time that single front chainring became a thing and everyone started to get crazy about converting to a one-by system.
What happened to that, you might ask? Well, back then it ended up being just an unjustified trend. The main reason for that trend was, same as now, simplicity. Simplicity and low weight are really good things to have on your bike when your intent is to either have fun or race professionally.
Unfortunately, technology wasn’t up to the task to sufficiently replace the gear deficit of a single chainring.
How are things different this time? Well, for a start, we are able to produce and fit much larger cassettes in the back than we used to before. The whole drivetrain technology improved a lot to enable these upgrades. When I say upgrades, you should take it with a pinch of salt because not all manufacturers were able to produce high gear and high range cassettes that work properly.
Since this 1x drivetrain trend appeared once already, this time we should be wondering if every brand managed to surpass those already mentioned technological barriers.
I haven’t had the opportunity to test everything on the market but I have experience with the more common setups. These setups include parts from popular manufacturers like Sram, Shimano, Race Face, Sunrace, and Wolf Tooth for the front chainrings which have become go-to brands for this type of component.
Not even all of these brands are doing everything perfectly when it comes to 1x drivetrains, a part of Sram of course who kind of sets the standard and invents new stuff regarding one by drivetrains moving forward. Shimano usually takes a year to follow in progress but when they finally develop their drivetrains they work even better than Sram’s ones.
Sram developed a 500% range 12-speed cassette that is actually working without dropping the chain when pedaling backward before anyone else did. Only in recent time, Shimano is following through with their 12 gear cassettes available in XTR, XT and SLX groupsets. Why would you pedal backward? Well, in some cases when going downhill or during some techniques you need to turn your pedals backward in order to keep a proper position for the next obstacle or next technique you wish to use on the trail.
Other manufacturers which I mentioned developed parts to make this system work but either with a lower range cassette or much lower quality and durability. While lower gear range is perfectly fine for a specific type of trail, it lacks in versatility. Lower teeth range from the lowest to the highest gear will result in either not having the easiest climbing gears or stroking out on a fast downhill and level ground.
Is 1x Drivetrain Good For You?
The fact that there is a 50/50 debate going on for several years about this already, only proves that having a single front chainring isn’t for everyone.
There are different kinds of riders. Same as in any other sport, some rely more on technique, some on efficiency, some on strength, and so on.
Really experienced and pro riders prove time and time again that they can win races riding pretty much anything but there are important differences nonetheless.
The average rider needs to account for all of these things in order to choose a bike that will not only fit their style and capabilities but allow them to have the most fun they can have.
As I mentioned at the beginning, 1x drivetrains offer simplicity and low weight. While low weight isn’t that important for most casual riders, it is actually a crucial thing for technical rides. The less weight your bike has the more control you will have over it. It is that simple.
Simplicity doesn’t seem important at first but unless you are really skilled with proper shifting and that requires a lot, and I mean a lot of experience with the same bike, you will have much more fun without a front derailleur.
You don’t want your chain getting stuck or drop down by not shifting on time or shifting poorly on technical parts, and that actually happens a lot when you are focusing on what’s in front of you.
1x drivetrains also require a bit more strength and endurance. Not only the range is smaller, but the jumps between the gears are larger as well. That means you may not always have the perfect gear to choose. You will have to put more effort and that means losing more energy to overcome specific trail parts. This proves true mostly on less technical types of trails, especially in cross country racing, while in more technical or downhill riding, larger gear jumps are actually not affecting you that much. That’s why this 1x trend is proving to be completely valid this time around.
Why More And More Frames Are Designed For 1x?
Bicycle manufacturers are creating frames specifically designed for 1x drivetrains. Why would they limit their bikes to 1x?
Well, the answer is simple. They are manufacturing bikes for a specific trail type and purpose. Since new technologies let us use single chainrings for most rides, they have taken the opportunity to have more freedom with frame design.
One by drivetrain takes less space and with less complication. As a frame designer, you are able to improve other things around it.
Most of these bikes have much better geometry than it was possible before. The part of the frame where the front derailleur used to be attached is not only stronger now but allows for a better rear suspension mounting and position. Frames are also improved by shorter chainstays for better performance.
Most people I asked about if they feel the geometry improvements said that this tremendously improved riding efficiency. Not only that but geometry improvements go so far that bikes from different brands today feel much different to ride than they ever did before. Some brands even started developing new types of mountain bikes. For example, the recent appearance of reinvented Top Fuel by Trek started a new era in trail/XC capable full suspension bikes that other brands are starting to follow as well.
Some people might find it useless, but since enduro and trail bikes are becoming more and more similar in capability, this is a welcomed novelty, in my opinion. As far as I know, this should suit most people who are casual riders that prefer XC riding with a bit of no-jumps trail riding now and then.
Where Should You Use 1x Systems
I’ve decided to start about downhill for a reason. All of the mountain biking is slightly changing towards downhill / high-speed performance. This is closely related to the one-by trend in recent years.
As some people say, everyone is a downhill rider, they just don’t know it yet. This is true to some extent and it’s highly relevant for this topic because downhill bikes are using specifically developed one by drivetrains for years already.
Therefore, improving mountain bikes for speed and downhill riding requires adapting to 1x drivetrains. That simplicity outmatches everything else in terms of importance and benefit when going downhill.
Enduro bikes are most people’s favorites, including myself. Most brands offer two bike models for enduro racing.
Usually, there is one that is more downhill oriented. These bikes are equipped with one by drivetrains because they want to mimic downhill bikes with more suspension travel but keep the aggressiveness and cost down. Â While maintaining a decent amount of versatility.
The other one would be something like a good all-around bike. These used to come with 2x drivetrain unless there is a wide range 1×12 setup from Sram. Nowadays, all of them come with 1x drivetrains, especially since Sram and Shimano introduced one by to their cheaper drivetrain ranges. I personally love Sram NX 1×12 on my all around bike because it is affordable with amazing 1x performance. Although, the rear mech isn’t as durable as it should be. I love to pair this groupset with a GX 12-speed Derailleur. Shimano, in my opinion, did a better job at their cheaper 1x drivetrains. However, Sram is still my preference for lower-end groupset because of lower price and weight.
I’m using cheaper NX because this is the bike I’m using the most, even for riding to my day job and back, so wear costs would bankrupt me. If you are wondering, it’s Trek’s Remedy and it is an excellent all arounder I can have fun anywhere with.
Trail bikes are the original all-rounders. They still hold that position for anyone that’s not too much into freeride or downhill riding.
These bikes used to use 2x drivetrains most of the time because they excel at long distance trails and climb very well so you will need that gear choice to stay in your comfort zone. However, they started migrating towards more technical trail riding and became similar to enduro bikes.
Most 1x systems used to limit the potential of this type of bike, however, nowadays it can be made into a viable setup. The only problem that still appears is that you have to adjust the number of teeth on your front chainring for the trails you are riding the most.
In my opinion, out of all mountain bike types, except hardtails, trail bikes lose the most with the 1x drivetrain just because most of us expect them to do everything, even ride well on the road to the trail and back.
Cross Country / XC
This is a kind of controversial category in my opinion, because if we are talking about actual racing then 99% of the time you will be better off with two by drivetrain. That is of course unless you are experienced enough with the trails and your gears to know exactly how fast you can go with one chainring on a specific trail. And if you can actually benefit from that lowered weight.
On the other hand, if you are a casual XC rider that uses this bike only for Cross country, you can enjoy far more with the simplicity of one by drivetrain.
Cross country trails, like classic trail riding, feature a great variety of climbing sections as well as sections where you can use high speed. You can easily end up using a lot of your strength and energy with a single chainring but casual riding is all about fun, not endurance.
The same case about limitations as in trail riding can be made here as well. These bikes are usually expected to do everything, especially everyday riding and 2x will always do better in that scenario.
When is 2x Actually Better?
The most important would be your skill level. If you are experienced enough you may prefer to have more gear options instead of simplicity.
If you are not particularly strong you may not be able to constantly stay out of your preferred gear ratio with a 1x drivetrain. And more importantly, you may not use some moves properly and efficiently.
Another reason to use 2x would be that you are using that bicycle for a variety of different trails. If that’s the case, then you need to be able to have all the gear choices for different types of riding.
Lastly, I would mention, everyday usage. Don’t know about others but I live in a city where there are hills and long straight roads so I need both, low and high gears. In other words, I need to have the biggest range possible on my everyday bike. That is of course if, like me, you don’t have a specific bike for this purpose alone.
Claims and Concerns
I’ve gathered some information about what people think of one by drivetrains. These are mostly claims and concerns which I have the necessity to clarify. This is all from my own experience and my own logic. It may not be true for every possible situation.
Apart from things I already mentioned like weight saving, simplicity, and lower gear ratio, there are some common claims and concerns about switching to 1x drivetrain.
The first thing you may hear is that you can’t climb at all with a single chainring. While this might have been true some time ago, today not so much. Especially with high range 12-speed cassettes. You will still lose a bit on either side of the gear range but if your legs are strong it becomes quite irrelevant.
There is a valid concern for some people and that would be the cost. One-by drivetrains are generally more expensive. This, as well, was a major problem some time ago. The biggest problem was the cassettes. 11-speed cassettes were really expensive and properly working 12-speed ones didn’t exist. It’s a bit different these days since you can have a 12-speed cassette in the back by Sram NX for around $100.
Better ground clearance at the front chainring can be a valid point. I use 32 teeth mostly and that’s significantly smaller chainring than 36 teeth that’s usually found on 2x setups. 3x uses even bigger chainrings so that is a big plus on the side of clearance.
This helps you a lot when going over larger obstacles. Especially if you make a mistake, there is less chance to get stuck on something and injure yourself. Not to mention the damage you can do to your bike. Believe me, I’ve been there quite a few times.
More Space on Handlebars
Losing the left shifter means you get more space for any other important upgrade. For example, I’m pretty active on my dropper post. I adjust the height all the time during a trail ride.
Dropper posts are an amazing upgrade to your bike and if you learn how to use it to your advantage, it can make trails much more enjoyable and your rides more efficient.
It’s not that you can’t have both dropper post lever and a shifter on the same side, but it’s much easier to use when it’s in the position where shifter used to be. For me, every other position means that I need to loosen the grip on my handles in order to use my dropper.
Maybe that won’t be the problem for someone with larger hands but I like to keep my riding safe and comfortable. Same goes for any other upgrade you wish to have there.
The Stronger You Are The Better
Someone might claim that using and increasing your strength by riding 1x will make you a better rider.
As much as I like one by drivetrains, I wouldn’t say this makes you particularly stronger by itself. You need to gain strength elsewhere and then you can benefit from it.
The other thing is, strength will make you more capable but it alone won’t make you a better rider. It always comes down to learning and gaining skill.
Considering everything, only spending a lot of time on your bike can make you a better rider. Everything else is just about how you prefer to use that skill.
Having a single chainring at the crank means it will have to carry the load by itself. Unsurprisingly, this comes at the cost of increased wear over time. The costs of running one by indeed are a bit on the upside but everything great comes at a cost.
Don’t let this scare you away from enjoying your rides though. By my estimate, the wear is not that drastic as some mountain bikers claim. Also, the chainrings are not as expensive as they used to be. I wouldn’t worry much about it.
Unwanted Gear Change
This used to be a huge problem. Because of the chain line not being straight on 1x drivetrains, older and â€œcheaperâ€ cassettes used to drop gears when pedaling backward.
I find this happening quite rare these days. As a matter of fact, I’ve never even seen this happen on any properly set up Sram 1×12 setup, and I’ve only had it happen twice on a bit older 1×10 XT from Shimano.
Conversion to 1x Drivetrain
As far as conversions to 1x go, I’ve tried pretty much everything that’s relevant on the market. There are some easy to do ones but in every case, there are things and problems to be aware of.
By this point, I’ve made it clear that every rider should understand the gear ratios and what he can get from converting. For me, this was easy because I’m working as a bicycle mechanic and therefore I have the opportunity to test pretty much everything that exists. For less experienced people I recommend trying the ratios before converting.
You can always ask for a test ride at the nearest bike shop or find someone to let you try on their bike.
I used to run 1x with a chain guide upfront. This was kind of mandatory back then because we didn’t have clutch derailleurs and specifically developed narrow-wide single chainrings.
For people who are new to this kind of thing, a clutch is a stop mechanism on your derailleur which prevents it from moving forward and slackening the chain. That way the chain stays tight on the front chainring. It’s amazing when everything is properly set up but it tends to make a rear derailleur sensitive to cable tension. If it slackens just a bit it becomes terrible at shifting. In addition, any bending of a derailleur or its hanger causes even more problems than usual.
There is one other amazing invention for one by setup and that would be narrow-wide chainrings I mentioned above. The teeth are made with every other tooth being wide so that the chain fits tightly. From what I’ve tested this together with a clutch is a much better option to have than chain guides. For some more experienced riders, bigger and more technical jumps still require chain guides in order to keep the chain locked in.
Chain guides are still widely used as lots of people have derailleurs without a clutch and are not willing to spend too much money on converting to 1x.
Recommended Parts And Tips For 1x Drivetrain Conversion
I’ve done several successful conversions to a 1x drivetrain. Seems quite straight forward at first but it’s far from being simple. The biggest problems you will face is adapting everything to your frame since the chainline is kind of a big deal with 1x drivetrains. If you do this wrong then you won’t be able to adjust high gears properly and your chain will wear out quickly.
To give you a short answer, the proper chainline for non-boost frames is 48-50 mm and 51-53 mm for boost frames. The tricky part is adjusting this with components from different chainring manufacturers.
To keep it simple, I would always recommend sticking to Sram for conversions. They offer the simplest solutions and the least complications for adapting chainline.
1x MTB Cranksets
Sram’s cranksets are compatible with boost and non-boost frames. They’ve made this very simple by making chainline difference with their direct mount chainrings.
My favorite crankset choice is NX Dub Crankset 32t simply because it’s affordable and features all the best Sram’s technologies with 32 teeth. That one I linked comes with a Boost chainring which is the most common choice these days. However, If you need a non-boost one, you can get a different chainring here where the 6mm offset is for non-boost frames and 3mm offset for boost frames.
32 teeth chainring is the most commonly used one, but most frames will work with 30 or 34 teeth as well, depending on what suits your way of riding more.
1x MTB Cassettes
To keep the costs down I would use a cassette that fits HG freehub body unless you already have some other freehub body.
My top choice would be NX Eagle 11-50 12-speed cassette. It rivals all those budget cassettes in price and beats them in quality. Also fits the best with other Sram parts.
If you need more range though, you might consider going for a GX Eagle 12-speed cassette which has a 10-50 gear ratio. Doesn’t seem like a big difference but it’s quite a lot in high gears. For Sram’s cassettes with 10 teeth smallest cog, you will need an XD driver freehub body. Be aware though, you need to match XD freehub body with your hub manufacturer as they all have different standards. You can usually find one manufactured specifically for your hub brand or even model.
For those who want to stick with 11-speed 1x systems in order to keep their derailleur, shifter, and chain, Shimano offers high-quality cassettes in XT and SLX series. However, they go only up to 46 teeth with 11 teeth for the smallest cog. As a solution, there is a SunRace CSMX80 11-speed cassette with 11-50 range.
When it comes to chains, it’s pretty straightforward as to what fits and what does not. You should always try to fit the chain from the same brand as your cassette.
Brands that make cassettes but do not make chains usually fit equally with every major chain brand like Shimano, Sram or KMC. However, brands that do manufacture chains often have some systems in place to make them work better with their cassettes. Usually, those involve some specific cassette shifting lines and angled edges on chain links for better shifting performance.
Since chains are the first to wear out, I like to invest a bit into a good durable chain. Especially if you consider that a worn-out chain wears out the cassette much faster. A durable chain makes the whole drivetrain almost wear-proof.
My favorite choice is always and forever the same XX1 Eagle 12-speed chain.
1x Shifters and Derailleurs
Shifting performance is a bit subjective. From person to person, it can mean a great deal in enjoying a ride or not be important at all.
The important thing to do is always fit derailleur with a shifter from the same brand. Preferably from the same series as well.
It’s usually a 50/50 rivalry between Sram and Shimano. In my opinion, Sram shifters and derailleurs are more durable and easier to maintain, on the other side, Shimano usually shifts better for the same price.
I prefer Sram because of durability and maintenance, and since I’m not racing, a bit better shifting won’t make me a better rider. I prefer riding with less headache that Sram offers me.
Let’s Wind Up
I’ve felt that lots of newer riders seem to blindly follow the trends and then limiting themselves without even realizing it. I’ve made this article simply to share my experience and my opinions about it.
The reality is, there is no “best drivetrain.” I’ve literally seen people prefer cheaper 2x drivetrains over much better 1x setups, even some custom made stuff that worked better than your average Shimano drivetrain.
That may sound unbelievable but really it isn’t. It’s all very subjective and we should try and adjust the components with our skills and limitations.
Also, one thing that we all forget too often, better bike or a better drivetrain won’t necessarily make you enjoy your riding more. It’s way more important to ride your bike regularly than having a flashy bike that stays in the basement.
All in all, each setup has its good and bad sides and without trying it you can’t really know.