Ahead of Unbound 2024, Ben Delaney looks back on more than 15 years of gravel tech development
It began, as most things do, with the simple idea to try something new – using gear intended for another purpose.
Fast forward to 2024, and gravel race tech is so specific – and often so expensive – it has more or less become a meme of itself.
As gravel has developed from an ultra-fringe, underground activity to an ultra-trendy pursuit (within the confines of the cycling world), scores of companies have jumped on the bandwagon.
Some have created legitimately innovative tech based on years of first-hand experience, careful R&D and a sincere interest in building better gear for gravel riders.
Others have simply slapped the word ‘gravel’ on existing products – socks, bar tape, saddles, you name it – and hoped to cash in on the trend.
Here, as part of BikeRadar’s Gravel Racing Week, we look back on where gravel riding started, where we are now and how we got here. We’ve enlisted some of the riders who were in at the ground level, and who now work at companies such as ENVE, WTB and CamelBak, driving the design of the best gravel bikes and gear.
Where it all started
When was the very first gravel race? Some would cite Paris-Roubaix, the UCI road race that spans two dozen-plus cobblestone sectors and was founded in 1896. Some would point out that the Tour de France began on unpaved dirt roads, with riders tackling the French Alps on fat tubular tyres, with the first edition in 1903.
But most track modern gravel’s birth to America, with the introduction of events such as Trans Iowa in 2005, Dirty Kanza (now Unbound Gravel) in 2006 and Almanzo in 2007, where riders registered for free with a simple postcard entry.
The gear often consisted of cyclocross bikes, which had the widest tyre clearance of drop-bar bikes at the time.
The fields were small, by any standards, and the rules consisted largely of the honour system.
Gravel tech pioneers
Dan Hughes won the first ‘DK’/Unbound Gravel on a custom frame made by Brent Steelman in Redwood City, California, that could take a – then enormous – 40mm tyre.
Hughes used Campagnolo shifters and a Campag rear derailleur with a Shimano Dura-Ace crank. In subsequent editions – he secured three more victories and finished more than 10 times – he used narrower tyres until stock frames expanded their clearance.
Hughes was one of the first inductees into the Gravel Hall of Fame in Unbound Gravel’s hometown of Emporia, Kansas, along with Trans Iowa founder Mark ‘Guitar Ted’ Stevenson, Unbound Gravel’s Kristi Mohn, Almanzo founder Chris Skogen, The Mid South founder Bobby Wintle, Rebecca’s Private Idaho founder Rebecca Rusch and Gravel Worlds founder Corey Godfrey.
Yuri Hauswald was a 2023 Gravel Hall of Fame inductee, in part for his 2015 Unbound Gravel win – a time when purpose-built gravel bikes barely registered.
“My first ‘gravel’ bike was Marin’s 2012 Cortina, a carbon cyclocross bike that I could barely squeeze 38s on,” Hauswald tells BikeRadar.
“This was the rig I did my first Unbound on in 2013. I was running a cyclocross tyre from WTB, quite possibly their Cross Boss. Tubeless technology was still in its infancy at this time, so getting your bike set up that way always involved some higher alchemy.”
“When I won Unbound in 2015, there really wasn’t much gear that was gravel-specific yet, beyond Salsa’s Warbird,” adds GU community manager Hauswald, agreeing that ‘gravel-specific’ wasn’t even a term yet.
“I still had to squeeze 38s on my bike in 2014, and for 2015 I ran Specialized’s Trigger Pro, which may be the most successful tyre at Unbound, since both Dan Hughes and Rebecca Rusch won many of their titles on that tyre.”
Adventure adaptations
Neil Shirley, a former pro road and mountain bike racer, who is now ENVE’s marketing director, was an early leader in gravel racing. He won events such as the Belgian Waffle Ride in 2013 and 2014, and Gravel Worlds – the Nebraska-based event born in 2010, not the new-aged UCI World Championships – founded in 2015.
“My first gravel bike was custom-made for me in 2012 by Calfee to take on Crusher in the Tushar (an event created in Utah by former road pro Burke Swindlehurst, that is now part of the Life Time Grand Prix series),” says Shirley.
“They started with a bright orange custom Dragonfly with ‘adventure’ geometry built at Calfee’s La Selva Beach, California, workshop. The final product would go on to help influence the market long before most brands even realised gravel was a thing.”
Shirley says the Dragonfly used geometry modified from traditional road to ‘adventure’ for more stability, slightly relaxed handling and clearance for up to a 35c tyre.
“It’s laughable to think about the high tyre pressures and narrow widths accepted at the time,” he adds.
The build used ENVE’s 29-inch XC tubular rims laced to Chris King hubs, along with Schwalbe 33c tyres. “Because cyclocross tyres were limited to a max width of 33c due to UCI rules, finding a high-quality 35c was next to impossible,” says Shirley.
“Shimano Ultegra Di2 had just released in 2012, but unfortunately, it would be another year before a Shimano hydraulic road disc was an option. Cable-actuated, Avid disc brakes were matched to 10-speed levers with a compact 50/34 front chainring combo and an 11-32t cassette.”
Since then, gravel groupsets have come to the fore, with gravel-specific gearing to combine road speed with off-road climbing capability.
However, if you’re looking for a single piece of gear that changed the gravel game, then look no further than disc brakes. Not so much for their stopping power, but for how they freed frame makers up for more tyre clearance.
Add in tubeless technology, and we’ve come a long way from the good old/bad old days (depending on your viewpoint) of riding thick cyclocross tyres that maxed out at 35mm with inner tubes and perhaps a tyre liner or Mr Tuffy Strips in the hope of warding off pinch flats…
Gravel-specific everything
Fast forward to today, and many of the world’s best gravel riders will take to the Unbound start line on 45 if not 50mm tubeless tyres, 1x drivetrains, aero wheels and frames, skinsuits, aero helmets and hydration packs.
Gone are the days of gas-station stops and rummaging for food; this is the era of specialised nutrition, F1-style pit stops and gravel-specific flourishes on nearly every piece of equipment.
Gravel bikes themselves, for instance, have blossomed into such a large segment that there are two distinct types of gravel bikes: adventure gravel and fast gravel, with plenty of variance in between.
Adventure gravel bikes feature taller geometry, and mounts galore for racks and storage, while fast gravel race bikes boast aerodynamic shaping and minimal weight.
Suspension has also evolved, with short-travel, gravel-specific suspension forks arriving alongside proprietary ride-softening tech such as Specialized’s FutureShock headset, found on the brand’s Diverge gravel adventure bike.
“From 2013 to 2018, there was a significant shift in equipment, with the industry as a whole getting behind gravel,” Shirely says.
“The biggest improvement to product has come from tyre-width increases and tubeless compatibility, in addition to clearance on frames ever-increasing. Brands slowly began purpose-building the equipment.”
Shirley cites ENVE’s release of the G23 wheels in 2018, designed to add compliance to the rims for ride quality, with the leading edge of the rim also profiled to prevent pinch-flats.
It’s all about the tyres
Elsewhere, WTB had rolled out its first gravel tyre, the Nano 40, in 2014, followed the next year by a variety of all-road and gravel tyres.
Salsa, Kona, Cannondale, Rocky Mountain and Breezer were early adopters of WTB’s gravel tyres, according to Johs Huseby, WTB’s OEM sales director, who works with bike brands around the world, as well as being a gravel racer himself.
According to Huseby, 40mm and 45mm tyres are the most popular around the world for most bike brands.
“While there is a lot of talk among the top one per cent of racers about 50mm+ tyres right now, there are still very few brands specifying tyres this big,” Huseby says.
“For more adventure-worthy bikes, 50mm or bigger is the right direction, and I think we’ll see by next year the shift occur where the majority of bikes will be specced with 45s. There are a lot of bikes out there today that still don’t clear much bigger than a 45mm tyre.
“I think there is going to be a pretty big shift in the next two years where the more performance-oriented gravel bikes will be redesigned to fit bigger tyres than they do today.
“It was pretty recently that gravel race bikes were looked at the other way: they only fit up to a 42 or maybe a 44, but that shift is definitely happening quickly now towards bigger clearance.”
Away from tyres, geometry on the frames has also shifted, with slacker angles, and more comfort and compliance being built into bikes, even those designed for the pointy end of races.
Fuelling for the ride
Beyond tubing shapes and tyre profiles, the fuelling for gravel racing has changed tremendously since the discipline began.
Hauswald helped CamelBak develop a baselayer hydration system well over a decade ago and worked with the Californian company on modifying its running hydration vest for cycling.
“In 2015, the lightest, most breathable pack that CamelBak had in their line was a run vest/pack, so I decided to use two different versions of that because I suffer badly in the heat/humidity of the Midwest,” Hauswald says.
“After winning (Unbound) in their run vest, I let R&D know that I felt there was room to improve the pack so that it had more stowage, particularly on the chest straps, while still maintaining its lightweight, breathable features and access to jersey pockets.
“That nucleus of an idea sparked a collaboration that became the Chase Vest, which many don’t know was named after Chase County, Kansas.”
The latest innovation in gravel fuelling tech? Ahead of the 2024 edition of Unbound, Castelli has introduced the Unlimited Pro jersey, which incorporates a mesh pocket for a 1.5-litre bladder, saving the need to wear a dedicated hydration pack.
Going the distance
The fuelling technology has also changed significantly since the days of stopping to refuel at countryside gas stations.
“Back then, riders tried to eat and drink as much as possible, whenever it was possible,” says Mike Fogarty, CEO of sports nutrition company First Endurance.
“Some preached that you should drink your hydration and eat your calories, but that’s just not practical in gravel racing.”
Long sections of technical terrain on many gravel courses can heighten the risk of a crash if you take your hands off the bar, says Fogarty. “In other sections, even if you could take your hands off the bars, you’re so cross-eyed that you can’t get anything solid down. When you’re at threshold, you can’t chew/eat,” he adds.
Fogarty says gravel racing has played a big part in the evolution of high-carb fuelling, thanks, in part, to the distance covered in many events.
“The longer you go, the more important your nutrition becomes,” he says. “This is not just for pros either. It’s not uncommon for a lot of riders to finish 3+ hours after the winners. Fuelling is as, if not more, important for these riders because of the significant amount of time they’re racing.”
Like pretty much all gravel know-how, a lot has changed over the past 15 years and that extends to nutrition.
“There have been revolutionary advancements in technology, ingredients and endurance research,” says Fogarty. “New carbohydrate sources have made it possible to successfully consume more carbohydrates/hour than ever before so you can race harder, longer and without GI distress.
“And electrolyte technology now allows riders to get clinically effective doses of all the electrolytes they need to prevent cramping and dehydration without any negative side-effects.”