It used to be simple. If you were doing a mountain bike race, you rode your mountain bike. If it was a road race, a road bike was the choice. Lots of gravel events are blurring the lines and making bike selection tricky. Having just returned from one of these dirty events — Grinduro in Quincy, California — I started musing about bike choice.

To begin with, here’s my quick video primer on what Grinduro is.

I also raced Crusher in the Tushar and Barry Roubaix this year and can say that Grinduro is the most unconventional gravel event I’ve done. However, I saw an interesting blend of mountain, cyclocross, gravel, and even road bikes in all three races.

Here are the three “Cs” to picking the right (ish) bike and gear for these wacky events.

1. Comfort

Most of the gravel races I’ve done have been around four to five hours. I wouldn’t recommend sacrificing comfort for the sake of speed. In particular, at Crusher I wore some superlight MTB race shoes, and by the end, my anklebones were killing me. I was especially happy with my bike at Grinduro. Enigma, a British framebuilder, sent VeloNews a steel 650b bike that really took the edge off the route’s rough terrain between the more compliant frame and 42mm-wide WTB Resolute tires.

2. Confidence

I grew up racing mountain bikes and have done more cyclocross races than I care to remember. For me, a drop-bar bike is no problem, even on Grinduro’s wild final descent, which is essentially a mountain bike trail. However, if you’re not as comfortable on loose terrain, there’s no shame in riding a mountain bike. Carl Decker rode a 29er hardtail mountain bike to victory at Grinduro. I saw some guys who were absolutely crushing it at Barry Roubaix on mountain bikes. Don’t get hung up on aesthetics or groupthink about what a gravel bike “should” be.

3. Capability

The two key components in mind here are gears and tires. Sure, other components play a role, but hey, we don’t have all day here. When it comes to shifting, having a very easy bail-out gear is essential at events like Crusher and Grinduro. Barry Roubaix’s hills are steep but not too long. Still, at all three, I went with a single-ring crankset and a 10-42 SRAM cassette. A 42-tooth chainring is usually right for most riders. Naturally, if you need an easier gear, a 40t ring would help you spin on the steep stuff.

As for tires, tubeless with tire sealant is practically essential for rough, rocky days like Crusher and Grinduro. Go wide, make sure you have some treads (like those WTB Resolutes I mentioned). Don’t sweat a slight loss in rolling resistance. I got a flat tire halfway through Crusher — trust me, it’ll slow you down more than a few extra knobs.

I took a few photos of some notable bikes at Grinduro. I’ll cop to being a mediocre photographer and fairly exhausted from a long day of riding, but perhaps you’ll be inspired when you build up your gravel rig.

Grinduro bikes
Former road pro Ted King was on Cannondale SuperX with 40mm MSO tires and a stout 44-tooth chainring — don’t try this at home unless you can push some big watts. Photo: Spencer Powlison | VeloNews.com
Grinduro bikes
I’m not sure who rode this Marin Cortina AX 2, but the black/purple fade and matching Lauf fork was stunning. The 40mm WTB Nano tires were a popular choice in California. Photo: Spencer Powlison | VeloNews.com
Grinduro bikes
The Lauf Grit is one of the few gravel-specific forks with an unconventional carbon-fiber leaf spring. Photo: Spencer Powlison | VeloNews.com
Grinduro bikes
Defending champion and SRAM employee Duncan Riffle rode a custom-painted Santa Cruz Stigmata. It had 50mm Clement (now Donnelly) XPlor MSO tires, which feature low-profile knobs. Photo: Spencer Powlison | VeloNews.com
Grinduro bikes
Riffle’s bike was first painted purple, then it got the gold treatment. Remember how I said Decker won the race? Well actually, he tied for for first with Riffle. Down to a tenth of a second! Photo: Spencer Powlison | VeloNews.com
Grinduro bikes
Meredith Miller was aboard her Canyon Inflite CF SLX, which she raced in September at CrossVegas. It had a wide-range 10-42T SRAM cassette for the steep climbs. Photo: Spencer Powlison | VeloNews.com
Grinduro bikes
Geoff Kabush rode his Scott cyclocross bike with a few gravel-friendly modifications. Photo: Spencer Powlison | VeloNews.com
Grinduro bikes
One of the key changes Kabush made was the addition of 40mm Maxxis Ravager tires. Unfortunately, the Canadian wasn’t immune to flat tire problems, as evidenced by the sealant mess on his rear wheel. Photo: Spencer Powlison | VeloNews.com
Grinduro bikes
Katerina Nash was in a punchy mood after a fun day at Grinduro. Not surprising, since the Clif Bar pro won the women’s category. Photo: Spencer Powlison | VeloNews.com
Grinduro bikes
Nash’s ‘cross bike has a shout-out to her teams CX Fever Grant program. As for tire choice, Nash went with 40mm Maxxis Ramblers. Photo: Spencer Powlison | VeloNews.com
Grinduro bikes
The CX Fever Grant is a chance for junior women to learn from the Clif team at Continental Championships in Louisville, Kentucky in early November. Photo: Spencer Powlison | VeloNews.com
Grinduro bikes
Here’s the 650b Enigma I rode at Grinduro. It might be overkill for most gravel rides, but it’s fun and can handle some legit mountain bike trails. Photo: Spencer Powlison | VeloNews.com
Breadwinner
Similar to my Enigma, Breadwinner brought its new G-Road to Grinduro. The 650b gravel bike has a steel IGLE fork and room for 2.1 tires, like the Schwalbes shown here. Photo: Spencer Powlison | VeloNews.com