Best 1x gearing options for gravel

99 out of 100 times when people ask us about the best gearing options for gravel, they really mean “how can I get a big enough gear range”.

So here we will discuss how to squeeze the most gearing options out of your Shimano, SRAM or Campagnolo 1x drivetrain. There are many options, so just scroll down to the set-ups that most interest you.

For the 2x options, you can find those in a future post.

Step 1 – Reduce the chainring

Seeing what gears people still ride with, it bears repeating. Do you really need that biggest gear? 53×11 is big enough to win the Tour de France. Now reduce that based on our power output relative to the top pros, the lack of domestiques and the slower gravel surface (and even if we ride on asphalt, unlike for the Tour our routes don’t get freshly paved just because we plan to ride there).

Then throw in other road users for good measure and realize that puncture protection is more important since most of us don’t have a team car on our Saturday ride! Finally, take into account that your gravel tires have a bigger circumference than your road tires (a wider tires is also a taller tire).

Soon you realize that a 20-30% gear reduction is not unreasonable (that would mean roughly a 42×11 or 38×11 as your top gear). Now, most won’t want to go that far and you don’t have to, but more likely than not your top gear sees little use right now.

Even for the descents, the advantage of having a large top gear is limited. If the descent is technical, your speed won’t be that high. If the descent is fast, you won’t be pedaling at your terminal velocity anyway. The top gear only determines at what point you can stop spinning and start coasting. You’ll keep accelerating regardless. That last little push with the bigger top gear provides just a small advantage, in the end any gear is rendered useless.

If you currently ride a Di2 or AXS electronic drivetrain, you can actually get a read-out of how much time you spent in each gear. Whenever I ask people to do that, they are shocked by how little they use their biggest gear(s). And that read-out even exaggerates the usefulness of your biggest gear because it also includes the time you spend in it while coasting down the hill.

For gravel I ride with 34×11 as its biggest gear. Even when I ride that gear on the road, I rarely miss having a bigger gear (sometimes I do, but it’s surprisingly rare). At 120rpm I get to 45kph, more than enough on the flats. Going downhill, I just enjoy the scenery as gravity pulls me towards terminal velocity.

I’m not suggesting you go down to a 34T, but there is room to reduce your top gear and gain a much more useful bottom gear. The most popular single ring for gravel is the 42T, while the 40T and 38T share second place.

So give that some thought; getting your top gear in line with what your legs really need is the best first step towards perfect gearing.

Step 2 – Increase the cassette range

If you don’t want to reduce your top gear – or in addition to that reduction – you can get a wider cassette. Sounds simple, but depending on what rear derailleur you have, there may be some tweaking involved. So let’s list it by the rear derailleur you have.

11-speed SRAM medium cage

If you have a medium cage SRAM rear derailleur on your gravel bike, you most likely have an Exploro Speed with a Force 1 rear derailleur and an 11-36 cassette. Which means SRAM tells you that is as big as you can go. If you want to believe that, there are two options to still increase your range:

1. e*thirteen makes an 11-speed 9-34 cassette
2. Leonardi has a 9-36T cassette

Because these cassettes start with a 9T cog, they all need an xD or xD-R driver. Additionally, you have to decrease your front ring by 18% to keep the same top gear. As a result, you will also get a smaller climbing gear despite the biggest cog not being any bigger than on an 11-36T cassette. So to compare:

But there is a second group of cassettes you can use to increase your range. And all you need to do is ignore what SRAM tells you about the 36T maximum cog spec for the medium cage Force 1 rear derailleur.

We’ve been testing all sorts of combinations in the lab and on the road, and we found you can use a much bigger cassette than recommended without a problem Here’s the list:.

Why would you want to run a medium cage over a long cage? With the mid-range cassettes, a medium cage offers crisper shifting. It also gives you better ground clearance.

11-speed Shimano medium cage

If you use a Shimano standard road derailleur, I would strongly suggest to consider getting something with a clutch. It will make life a lot better on rough surfaces by dramatically reducing chain suck.

If you have an Ultegra RX derailleur with a clutch, it has a maximum big cog rating of 34T and the Shimano 11-34 cassette is likely what you have.

That’s not a lot of range for a 1x drivetrain (if you have this as part of a 2x drivetrain, that’s a different story, see the next episode). In reality, this derailleur can go up to a 36T without a problem. It also has sufficient capacity to start at a smaller cog, so cassettes starting with a 9T cog are not an issue. All in all it means you have these options:

11-speed SRAM or SHIMANO long cage

For SRAM, this means you have an Apex1, Rival1 or Force1 rear derailleur. For Shimano this would be a GRX RX-812 (mechanical) or RX-817 (electronic) derailleur. The bike may have come with any number of cassettes, but most likely it’s an 11-42T.

These derailleurs are all rated for a 42T biggest cog. You can squeeze it a little bigger, but not much. For example, you could run the GRX derailleur with Shimano’s 11-46T mountain bike cassette (XT M8000 11-speed). It works, but it’s a little noisy.

Let’s put it this way: I would ride it if I really needed the bigger gear, but I wouldn’t sell it. With any of these hacks, you can expect and accept shifting that is maybe not quite as crisp or silent, but this 11-46T is a bit too far removed from the shift quality we are looking for. That said, several customers run the 11-46T on their GRX bikes and love it, so it is subjective.

However, if you want that sort of range, the solution I prefer is to go with the SRAM 10-42T cassette. Basically it gives the same range but without needing such a large cog at the end. Drawback is that you need to install and xD driver on your rear wheel.

To get even more range, you need to look at the other end of the spectrum, reducing that smallest cog to a 10T or 9T and then shrinking the chainring correspondingly to maintain your top gear. These are your options:

Note that these cassettes work roughly the same on Shimano and SRAM drivetrains. You do need to adjust chain length and the B-screw.

Your gear range can also be too big. The last four cassettes in the above table are probably not the best choice for most people on most terrain, as the huge range comes at the expense of big steps.

12-speed SRAM Rival/Force/Red AXS

The biggest SRAM cassette available for these rear derailleurs when they launched was 10-33T. That may work on some of your rides (and then it’s great as the steps are really small), but if you ever expand to tougher terrain it won’t be enough.

Then SRAM launched the “WIDE” range of crank, rear derailleur and cassette. The cassette ratio of 10-36T is nicer, and on 3T bikes it’s even possible to use the old SRAM rear derailleur with this new cassette – so no need for a new rear derailleur.

The next 12-speed cassette would be ROTOR’s 11-39. That one definitely does not shift well with either the standard or the WIDE rear derailleur (this is something SRAM, Rotor and 3T agree on).

12-speed SRAM XPLR

XPLR is the name SRAM uses for all their gravel-related products across various brands. So there is a Rockshox XPLR dropper post, some Zipp XPLR parts and there are SRAM XPLR drivetrain parts. Available in SRAM’s usual product levels, the XPLR parts are basically a longer cage rear derailleur and matching cassette. With this, you get a 10-44T range, enough for most routes for most people.

12-speed SRAM Eagle AXS

AXS is the “communication platform” SRAM has set up for their electronic parts to talk together. This means your AXS road shift levers can talk not only to Rival AXS, Force AXS and Red AXS rear derailleurs but also to Eagle AXS rear derailleurs from SRAM’s electronic mountain bike groups.

So you can combine your Rival/Force/Red AXS road shifters, crank & brakes with an Eagle rear derailleur, chain and cassette for a very wide gear range. And because it’s all wireless, switching out your rear derailleur is a snap. The bad news is, it will cost you, as the Eagle rear derailleurs are quite expensive compared to their road siblings.

Once you go this route, these are your options for cassettes (Note that SRAM’s 10-33T and 10-36T cassettes are too small to work with the Eagle rear derailleur, the B-gap will be too big):

One small note, the 10-33T cassette doesn’t work particularly well in combination with the Eagle rear derailleur. So should you want to have two different setups – one for speed using the 10-33 and one for tough routes using a bigger cassette – you will have to swap out the rear derailleur and chain every time (and potentially even the chainring). It might be worthwhile to use the 11-39T Rotor cassette for the fast setup instead, so you can do everything with the Eagle rear derailleur.

As in the case of 11-speed, the bottom 4 cassettes give you a very extreme range, likely more than you need.

13-speed Campagnolo Ekar

Probably the most surprising new drivetrain recently for many people, Campagnolo hit it out of the park with Ekar. 13-speed, great cassette combinations, no-fuss mechanical shifting and great brakes. A fantastic option for a 1x road bike and great for gravel too. I already wrote at length about what I like about Ekar for gravel, so here I will limit myself to the gearing options it provides:

In detail:

• 9-36T (9-10-11-12-13-14-16-18-20-23-27-31-36): 400% range is great, the only issue here is that the smallest chainring Campagnolo makes is a 38T right now. And 38×36 is a bit big as your smallest gear if the route gets really tough. On top of that there aren’t many alternatives for chainrings. One exception is our own 3T Torno crank which has the option of an Ekar-compatible 36T chainring. Otherwise, this is mostly for road, for stronger gravel riders, for less extreme terrain or for riders who mix a lot of asphalt and off-road sections.
• 9-42T (9-10-11-12-13-14-16-18-21-25-30-36-42): This is a big 467% range, so bigger than what I would normally call ideal. But when you really look at it, the 13 cogs means you can increase the range and cover more extreme situations (you could say it’s a 12-speed 10-42 cassette plus an extra 9T cog).This becomes clear when you see how the steps are distributed: the first 6 cogs are the same as on the 9-36T). Only in the climbing range do the steps get bigger, so it is very functional. You only need a 38T chainring to get a great top gear (equal to 42×10 or 46×11) and 38×42 is a great climbing gear as well.
• 10-44T: 10-11-12-13-14-15-17-19-22-26-32-38-44: This is a more traditional cassette range in that it starts with the 10T, and the 44T gives you that tiny  bit more climbing ability than most other cassettes topping out at 42T. Again the first 6 cogs are 1-step apart, so lots of options to dial in your gear.

Bonus: If you have a set-up of 1 bike with 2 wheel sets to combine road & gravel (or fast gravel & slow gravel), Ekar gives you a nice bonus. You can put the 9-36T cassette on your fast wheels and the 9-42 or 10-44 on your slow wheels.

Go with 10-44 and you get a 10% easier top gear with a 22% easier low gear. If you don’t want to give up any top speed, then the 9-42T cassette makes that happen while still giving you a 17% easier low gear.

Important notes

Linkset: I mention a few times that your chain should be 1 linkset shorter than recommended for the best shifting. By linkSET, we mean a set of 2 links, one narrow link and one wide link for a total of 1 inch in length. This recommendation is based on the “single-speed chain length” method, see below.

Single-speed chain length OFFICIAL method: Run your chain directly over your biggest (or only) chainring and your biggest cog. Do not run it through the derailleur. Take the chain length with the chains tight as you can over cog and chainring like this, and add 2 linksets (4 links, 2 narrow and 2 wide). Note that “as tight as you can” may not be very tight, because you always need to add links in pairs for 1x. So if the route around cog and chainring is just a tenth of a link longer than your chain, you need to add another “1.9 links” to make the chain whole again.

Single-speed chain length method HACK: The above is the official recommendation. For the big range cassettes in combination with the medium rear derailleur, you add only 1 linkset (2 links, 1 narrow and 1 wide) as described in the main article., instead of adding 2 linksets as mentioned in the official method. To avoid any confusion, this means with the hack, your chain will be shorter than with the official method by 1 linkset (2 links).

Correct chain length: Listed above are the ideal chain lengths for the best shifting performance using the single-speed chain length method. You do have some leeway here. If you use one of the setups only sparingly and can accept occasionally slower shifting, you can try to run your medium range and wide range cassette with the same chain length. In fact, with a bit of luck both of their ideal lengths are the same (since we recommend shortening the wide cassette chain length relative to the standard). In fact, in most cases (it depends a bit on the exact chainring size), the ideal length will be the 11-36T and the 11-40T cassette if you keep the chainring the same.

B-gap: When you start playing with these cassettes sizes and chain lengths, you will find that the B-gap (the gap between the upper pulley and the biggest cog has a big effect on how well it works. The exact recommendation for the B-gap differs from derailleur to derailleur, so best to check the manual for the exact number. And then you may deviate a bit to see if you can get the shifting even better.

xD vs. xD-R drivers: Whenever I say the cassette requires an xD driver, that means the xD-R driver will also work as long as the 1.8mm SRAM spacers is added between the driver and the cassette. xD and xD-R drivers are identical except for this 1.8mm length difference.Hope this helps, happy climbing!