Grinduro is not a typical gravel race. There is a heavy emphasis on shenanigans, food, and riding with friends. Other gravel events often make riders choose between these things or racing by timing the course from start to finish. Grinduro takes a slightly different approach, only timing short segments of the 70-mile course in Sullivan County, Pennsylvania. It functions much in the same way that enduro mountain bike races or certain Gran Fondo-type events.

The inaugural Grinduro PA featured four timed sections. A 4-mile rolling gravel road time-trial, a steep gravel hill climb, a gravel descent, and finally a technical singletrack descent full of stream crossings, rock gardens, and deep ruts. The first three segments were biased towards pedaling hard and going fast, making riders lean towards a gravel bike set up as light as possible. In contrast, the last timed segment would probably have been best tackled on a full suspension mountain bike with a dropper post. No single bike being perfect for the terrain is a bit of the Grinduro fun.

Our editors faced the same decisions as all Grinduro racers: Optimize for the majority of the timed segments and hope you don't lose too much time on the last one, or go the other route and hope to gain enough time on the singletrack to overcome the time lost on the faster sections. Let's see what they chose!


Our Editors and Their Grinduro Bikes

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Tara Seplavy

Up first is our Deputy Tech Editor Tara Seplavy and her Canyon Grizl CF. She equipped the bike with a SRAM Force AXS XPLR drivetrain, running a 38T ring up front and a 10-44T cassette in the rear. The tires were 700 x 43c Panaracer GravelKing SS (set up tubeless) on Zipp 303 Firecrest wheels with 39 psi front and 41 psi rear. Tara also ran a RockShox Rudy suspension fork and a Reverb AXS XPLR wireless dropper post. Because Tara races a lot of road and cyclocross, she (more or less) stuck with a road cockpit set up with a 110mm stem and non-flared 44cm drop bars.

Was it the right bike for Grinduro?

Overall, yes. I probably didn’t really need the suspension fork and maybe could have gone with narrower/lighter tires. The slicker tires were great for carrying momentum and efficiency on paved sections but just seemed chunky. Initially, I planned to ride a 40T up front, but the night before the race I swapped it out when I noticed the chainring had a broken tooth. I only had a 38T around, so I used that. It’s fortunate I did, as I’m glad I had that smaller gearing for the climbs. The dropper post was a game-changer though and it got plenty of use on the descents.

Anything you would change for next year?

For next year I'd like a lighter bike with a wider gear range. The suspension fork was overkill for all, but (at most) 2 miles of the 70 miles we rode. I would also opt for lighter tires, maybe 38s, but I’d stick with the slicks. To broaden my gear range, I would go with an Eagle rear derailleur and the 10-52T cassette with a larger chainring, so I could have a bigger gear for the descents and paved road sections.


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Rosael Torres-Davis

Our Special Projects Editor, Rosael Torres-Davis borrowed a Crust Bombora from a very kind friend (shout-out to Lauren Dodge of Automatic Racing). The steel frame was paired to a carbon Enve gravel fork and rolled on Enve AG25 gravel wheels and 700 x 42c Ultradynamico tires set up tubeless. Rosael had 30 psi in the front and 35 psi in the rear but lowered that a bit by feel during the ride. The drivetrain paired Shimano 105 hydraulic shifters with an XT clutch rear derailleur. She used a White Industries crankset with a 40T chainring and a 11-46T cassette in the back. Enve seatpost, stem, and flared gravel drops completed the build.

Was it the right bike for Grinduro?

I only had a chance to ride this bike once before heading to Grinduro but, overall I thought it was perfect for the event. Flared bars were new to me and so was the angled-in shifter position. To my surprise, I found that this setup actually took quite a bit of pressure off my wrists. I'm hoping to replicate this on a future build.

Having a greater than 1:1 gear ratio was really helpful for all the climbing we did. For the descending, the Ultradynamico tires, and their reassuringly large side lugs, gave me a lot of confidence when things started to get loose.

Anything you would change for next year?

Honestly, I don't think so. The bike was perfect as-is for me. For next year I want to work more on my technical skills to, hopefully, ride some of the rocky singletrack and creek crossings that I had to walk this year.


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John Hamilton

John Hamilton is one of our Photo Editors and was one of the many riders underbiking Grinduro. He rode a BlackHeart Allroad AL with 40mm Pirelli Cinturato Gravel tires stuffed into the aluminum frame and carbon fork. The tires were set up tubeless, running about 40psi front and rear. John's Blackheart had a 105 groupset with a 50/34T crankset and an 11-34tT cassette in the back. Basically, John raced a road bike with big tires.

Was it the right bike for Grinduro?

This was probably not the “right” bike for Grinduro but I still really enjoyed riding it. On 90% of the ride—everything from smooth gravel, the slightly chunkier gravel, even the muddy doubletrack—the bike was perfect. It climbed like a road bike, especially when out of the saddle. The course featured one technical, paved descent and the bike felt most at home in that spot.

There was one very steep gravel descent that got pretty rough. With the steep grade and some big bumps, I was pretty close to going over the bars once or twice and was really wishing for a more purpose-built gravel bike in that spot. Of course, the same goes for the singletrack section. Still, it’s worth pointing out that this was a very affordable build compared to many bikes at the event, and even as someone who doesn’t ride a ton of gravel, it got me to the finish line in one piece.

Anything you would change for next year?

Next year I'd love to have a lower gear. Something lower than a 1:1 gear ratio would be ideal. I'd also add a dropper post in a heartbeat. I know it seems like overkill but it would have made my life so much easier on the steeper bits of singletrack.


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Adam Schram

Adam Schram is our intern this summer and he rode Grinduro on a Cannondale Topstone Alloy from 2020. He kept the bike set up very close to stock, with Shimano 105 shifters and derailleurs. The bike featured an FSA crankset with 46/30T chainrings, mated to an 11-34T cassette. Adam swapped out the stock tires for a 40c WTB Raddler up front and a 37c WTB Riddler in the back. Both tires were set up tubeless with 30psi front and 35 psi rear.

Was it the right bike for Grinduro?

Mostly, yes. This generation of Topstone is definitely a more road-oriented gravel bike by design, but it's enough of a blank slate that I felt like I could make it work on the rougher roads and trails.

Anything you would change for next year?

My hands and back took a bit of a beating on the rougher sections. Hopefully, I can add in some compliance to help with that. Maybe some thicker bar tape or double-wrapped bars might be nice. I would also love a carbon seatpost for some added compliance. A clutch rear derailleur would have also helped me avoid some of my chain retention headaches. Also, I would have definitely appreciated an extra gear on some of the climbs. It sounds like I'll be trying to put together, more or less, a whole new bike.



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Theo Kahler

Theo Kahler is our Membership Editor and this was his first time ever riding gravel. Fortunately for Theo, he got to experience it on a top-of-the-line BMC URS 01 One. This URS, a Bicycling Best Gravel Bikes of 2022 winner, was absolutely stacked: SRAM Red eTap AXS shifting, XX1 Eagle AXS rear derailleur, and Enve G23 wheels. Theo used the stock 700 x 40c WTB Raddler tires. They were set up tubeless by our mechanic and Theo said he used “whatever tire pressure that was in there” when he took delivery of the bike shortly before the event.

Was it the right bike for Grinduro?

Well, I have never ridden gravel before, so my experience is limited but, I can’t imagine a bike riding better than the one I had. I was surprised at how light it was, especially toward the back. It handled the bumps very well and my hands and butt weren’t as sore the next day as I feared they might be. The bike handled everything that the course threw at me and I even felt like I got more comfortable throughout the weekend. Hopefully, BMC will let me borrow this bike again for my next gravel event!

Anything you would change for next year?

My experience is pretty limited but, I would have liked to have a harder gear for some of the long and fast gravel descents.


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Trevor Raab

Finally, here is the bike I rode for Grinduro Pennsylvania. It's a Pratt Frameworks Oyster Rock gravel bike, and the same bike I used for the 200-mile Unbound gravel race. Max Pratt builds frames in Providence, RI exclusively out of steel. It was built up with SRAM's Force eTap AXS shifters, XPLR rear derailleur, and a 10-44T XPLR cassette. I also used a Wolf Tooth 44T direct mount chainring and an Origin-8 chain guide to make sure my chain stayed put. The wheels were the Roval Terra CL and I used a Specialized 42c Pathfinder on the front with a Specialized 38c Sawtooth on the rear. Both were set up tubeless and inflated to 30 (front)/33 (rear) psi. My cockpit was from Zipp, sticking with my preferred Zipp SL 70 bars. For the seatpost, I used the Ergon CF Allroad carbon post. It has quite a bit of compliance, thanks to its split-leaf spring design and I sat on a Specialized Power Pro with Mirror saddle.

Was it the right bike for Grinduro?

I'm not sure if there is a "right" bike for Grinduro. I never had a moment out there where I wanted to be riding something else. There might have been a few moments where I might have been faster on something else, but I think that's the spirit of gravel or something. Most importantly, I had no mechanicals. Any gravel event where you don't flat or break something is a success in my book.

Anything you would change for next year?

I could go for a bigger set of tires. Something around 45mm wide with a bit more of a side lug would have been nice.

Headshot of Dan Chabanov
Dan Chabanov

Test Editor Dan Chabanov got his start in cycling as a New York City bike messenger but quickly found his way into road and cyclocross racing, competing in professional cyclocross races from 2009 to 2019 and winning a Master’s National Championship title in 2018. Prior to joining Bicycling in 2021, Dan worked as part of the race organization for the Red Hook Crit, as a coach with EnduranceWERX, as well as a freelance writer and photographer.