Life

Gravel Gearing: Horses for Courses

Choosing the Right Drivetrain for Your Gravel Adventure

Many people are discovering the thrill of exploring off road on a drop bar bike for the first time. Modern gravel bikes combine features from the worlds of road, CX, and MTB to create something versatile, fun, and capable. But “gravel” is a term that can mean many different things: for some, it’s using farm tracks to link together stretches of asphalt. For others it’s long stretches of packed dirt at altitude. For others, clattering down rugged and technical trails that might be easier, but less fun, on a mountain bike is the ultimate gravel experience. The gravel you encounter may be optimal with different geometry, body position, tire width, and, yes, gearing. Fortunately, SRAM offers something for every gravel experience. Let’s dive in:

CX/Gravel Racing

With multiple laps of a short course, all done at maximum effort, cyclocross racing requires a relatively narrow gear range. For our latest eTap AXS groupsets, pairing a 10-28 or 10-33 cassette with a 36, 38 or 40-tooth chainring will give an amateur the full range to tackle any CX course. For our mechanical 1x groups, an 11-32 or 11-36 cassette with a 38-42T ring is the go-to choice.

Strong riders who race gravel events in the front group will find that a 10-33 cassette paired with their choice of chainring is all they need to tackle a variety of terrain. SRAMbassador Roman Siromakha pairs a 10-33 cassette with a 44T ring on his Force eTap AXS bike, and uses it for road rides, gravel racing, and everything in between: “Most of my rides would be about 60%-40% pavement-to-gravel ratio. The 10 tooth cog allows me to sit on pavement with roadies and do a decent job at pulling the pack, but I've also raced the same set up at Rooted Vermont, which has some pretty good climbs. The gear ratio was sufficient for 99% of the stuff that I have ridden; I even took the bike on some single track.”

All-Road Bikes: Blending Pavement and Dirt

Who doesn’t want a bike that can do it all? OK, maybe not all, but we’re lucky to be living in a time with many choices for bikes that are fast and fun on pavement, while still plenty capable on technical gravel trails. A bike that can handle a huge range of activities needs an equally versatile drivetrain, and a 2x eTap AXS build with a 46-33 chainring combo mated to a 10-33 cassette covers it all. Cynthia Frazer of the gravel-focused team Meteor-Intelligentsia attacked her full calendar on the gearing. “I ride an Open UP and it’s my primary bike. I have a heavy dose of climbing in my backyard, but to get there I need to ride on the road for 5-10 miles depending on how I access the mountain. I run a 46x33 crankset and a 10-33 cassette. I spend 30-45 minutes climbing up and down the mountains in the Blue Ridge often using my lowest gear, and then race criteriums on my UP with the same gearing as I race Dirty Kanza or Croatan Buck Fifty.”

Bikepacking, Extreme Gravel, and More

Sometimes we want low, looooooow gears. Mountain bike gears. If you’re loading down your bike with equipment, or clawing your way up a long, loose and rocky climb, or saving your legs as you race across a continent, a drop bar bike with gears below a 1:1 ratio is just the ticket. Our mechanical 11-speed 1x drivetrains have changed the gravel segment since they were introduced five years ago. Pair a 10-42 cassette with a small chainring for a 420% range.

Want more range? Electronic shifting? Enter the mullet build. An Eagle AXS rear derailleur paired to road eTap AXS shift/brake levers allows the use of an Eagle cassette with 500% range. Pair  with a road chainring in the 38-42T range for your biggest adventures. SRAMbassador Chas Christiansen has ridden 1x and 2x AXS, but sticks with his mullet build for the gnarly stuff. “I am based on the west coast [of the United States] and most of our gravel events lean more towards MTB than road. This is where the mullet group really won me over: gearing more aligned with MTB-style technical gravel courses, the ability to juggle a wide gear range quickly for rapid climbs and descents. Having the "over-vert" option is a game changer as well, a 50t rear paired with a 46t front means that almost no hill is unclimbable, either in a fast paced gravel race where others have to dismount, or in an ultra-endurance race like Further, where you are crawling up very long steep dirt climbs fully loaded.”

The definition of road cycling is changing, but regardless of how a bike will be used, there’s a SRAM gearing option to suit it. For more on how our 2x drivetrains compare to traditional gearing, explore our story on X-Range gearing. For more on the benefits of wide-range 1x, there’s our mullet build story.