1X versus 2X?

Which Drivetrain to Choose for your Cobalt Warhawk?

Whether you're trying to decide how to configure your gravel dream bike or you’re just getting into gravel riding, deciding on the 1x or the 2x set up is the one of the first decisions you need to consider. (The other decision is between 700c or 650b wheels—see our 650B versus 700C wheel guide.) But how do you make that 1x or 2x decision?

To start off, what do I mean by 1x or 2x?

1x refers to the single front chainring on the crankset. These bikes typically have 11 gears total. One up front and 11 in the back, though 12 gears is becoming more common especially for the MTB crowd. 2x refers to bikes with two front chainrings and they are typically two front chainrings, and 10 or 11 gears in the back. The latest groupsets from SRAM offer 2x12 to cover a wide range of gearing.

The evolution in gearing and frames that can fit larger tires has really opened up options for riders to cross over bikes from road to gravel and gravel to single track. It also opened up new routes and rugged terrain without the need to have the fitness or skills of a pro rider.

How did we get here?

Over the last ten years, component manufacturers added the number of gears to bikes with 10, 11, and now 12 speed cassettes. This was key to providing riders with more gearing options to make climbing a bit easier. As they added gears some began to question the need for the front derailleur. Many riders would customize their bikes by adding a large range cassette in back and removing the left shifter and front derailleur to lighten and simplify the bike while keeping close to the same gear range.

What now?

What you’ll see most often is road bikes with 2x set up to allow for closer gearing ranges (less of a jump between gears) and a broad option for sprinting or hill climbing. Modern MTBs are often 1x setups and offer a wide gear range to both lighten and simplify the bike while allowing for a wide range to cover the lower speed, steep climbing and faster XC single track (as a matter of fact, SRAM stopped making MTB front derailleurs a few years back with the introduction of Eagle groupsets). But what about gravel you say?

How to Decide?

Which drivetrain should you choose? It will depend upon where you ride, and how you ride. The great part about getting a gravel bike is the flexibility with the type of riding you can do. Even if you’re road centric, an extra set of wheels can change the bike into a gravel grinder with a quick wheels swap to give you bike more suited for rugged gravel or even smooth single track MTB trails.

Both 1X and 2X drivetrains have added a new feature called a clutch to the rear derailleur. This takes the bounce out of the rear derailleur’s lower jockey and reduces chain slap and the chance of dropped chains on even the bumpiest trails. You’ll find clutched rear derailleurs only in Shimano’s GRX group set, and SRAM’s AXS. Be sure to consider this feature when choosing your drivetrain, because it’s definitely a feature.

Pick a 2x setup if...

You tend to ride or race on flat terrain. Live Florida or along the coast, where bridges and overpasses are your climbs? Prefer racing on fire roads in the Rockies or in Kansas? Those minimized jumps between gears on flat to rolling terrain will be much less jarring on a 2X drivetrain, keeping your power much steadier as the terrain rolls along.

You plan to ride your gravel bike much like a road bike. Enjoy having smooth transitions between shifts with slight cadence changes, and smaller steps between those gears will make you happy as you ride over rollers, up big climbs, and down steep road or gravel descents. Those that find themselves more often on pavement and riding in hillier terrain may prefer 2X for the more road-like shifting experience.

You want the option to climb steep hills. Generally speaking, a 2X drivetrain will provide a wider gear range. Meaning, its low gears will allow for easier climbing, while providing high gears that allow you to still pedal on steep, fast descents. With fewer gears, 1X tends to sacrifice a bit of end-range gear capability. Modern 1x12 set-ups can give riders a wide gear range that allows better flexibility on hills and flats.

Pros of 2x

• Greater range compared to 1x11 or 1x12
• Smaller gaps between gears providing smoother shifts
• Familiarity with set up

Pick a 1x setup if...

You ride your gravel bike a lot like a mountain bike. Many of today’s modern mountain bikes are running 1X. That means those MTB’ers used to riding technical or rocky singletrack on their mountain bikes are taking their new gravel bikes (like the Warhawk) out on the same trails. Familiarity with gearing changes of 1X for mountain bikers makes it a seamless transition for you.

Simplicity reigns. Without a front derailleur, a 1X front ring has deeper teeth, keeping that chain on over the biggest bumps on the trail. Since there is no front derailleur, that’s also one less thing to adjust, repair, or replace over time. Also, for those that want a dropper seat post, the left shifter can become your dropper post lever.

Weight savings is a premium for you. Are you focused on saving weight on your new gravel bike? A 1X drivetrain—with just one front chainring and no front derailleur—will save you about 200 grams; not a lot for a 19 pound bike but it all adds up and a 1X drivetrain can be a place to start.

You’re new to gravel riding. If you're not used to riding with left and right shifters and don't want to concern yourself with the complexity of a 2x setup, definitely go simple and focus on enjoying the ride!

You ride in poor weather. Again, fewer pieces to get out of alignment or clogged with mud, means less things to foul up, especially when the mud is like peanut butter.

Pros of 1x

• Lighter weight
• Simplicity
• Chain security

Still unsure? Our Cobalt team is ready to chat with you about gear choices when looking at how to build your next bike. Just visit the website, to make an appointment or drop us a line at info@cobaltbike.com