Another edition of Unbound Gravel is done and dusted. This year, the world’s largest gravel race saw bigger than ever fields, new course records and heaps of new gravel tech on display.
Mountains of new products landed just before or at Unbound, further cementing its position as the place to launch new gravel tech.
A great deal more tech raced by top athletes is still in the prototype stages or awaiting its official launch later this year.
From the ever-increasing importance of aero gear to a closer look at unreleased bikes, here are the key talking points from Unbound that are likely to drive wider gravel cycling in 2024.
Tyres – fatter is faster
In gravel’s formative years, tyres ranged in width from 35-38mm. Most racers began using tyres in the 40 to 42mm range as manufacturers expanded frame clearance.
Now, many of the top professional riders use tyres that are 45 to 50mm wide.
This year’s Unbound 200 winner, Lachlan Morton, sped to victory on the largest Vittoria tyres he could squeeze into his Cannondale SuperSix EVO CX SE frameset. Up front, he ran a 50mm-wide Terreno Dry, which didn’t leave much room for mud in the fork. Out back was a 44mm-wide Mezcal.
Despite the extra heft of these tyres, Morton set a new course record of 9hr, 11 min and 47secs.
I'm sure you’ve heard the tired (tyred?) joke about gravel bikes being mountain bikes from the 1990s.
In the case of Allied’s prototype frame ridden by Payson McElveen, there’s a grain of truth to it.
McElveen ran 2.25in Maxxis Aspen ST mountain bike tyres. These are true cross-country race tyres. McElveen's eighth-place finish proved the worth of wider rubber.
There was also variation in the tread riders used for Unbound. While conventional lightly treaded gravel tyres are most popular, some feel that, if course conditions comprise large and loose gravel, the minimal tread of most gravel tyres won’t provide much traction anyway, opting for slicks to improve efficiency.
For example, former Unbound champion Ted King ran 44mm-wide Rene Herse Snoqualmie Pass road slicks.
Keegan Swenson – the 2023 men’s winner and favourite heading into this year’s race – teased his bike setup with plump Maxxis Re-Fuse slick tyres ahead of the event, but swapped to conventionally treaded 700c x 45mm Maxxis Reavers for race day.
As for specific models, the Specialized Pathfinder still appears to be one of the most popular gravel racing tyres.
1x is gaining momentum, but there’s still a place for 2x
SRAM looks set to launch a new 1x 13-speed Red-level gravel drivetrain.
It appears to borrow heavily from the recently launched Red AXS road bike groupset.
As existing 1x13 groups from Rotor and Campagnolo demonstrate, adding a 13th cog makes the steps between gears more manageable for road and gravel riding. It’s likely SRAM has added an additional cog for the same reasons.
Virtually every SRAM-sponsored athlete was running it, so consumer availability can’t be too far off.
At this year’s Unbound, riders lucked out with weather conditions, with the course running largely dry.
Had it been as muddy as last year, 1x drivetrains may have had an advantage over 2x chainrings, because there’s no front derailleur to clog with mud and debris.
While we can’t attribute Morton’s 2x drivetrain with standard road chainrings as the componentry that cinched his victory, it certainly didn’t hold him back.
Ridley riders, including Belgian Arno Van Den Broeck, appeared to be racing a new TRP 1x12 drivetrain with a twist – these bikes looked to be equipped with Classified’s Powershift rear hub.
This internal gear hub provides riders with a range similar to a 2x setup, without the disadvantages of a conventional double crankset.
Given Ridley has a racing partnership with Classified, it’s highly likely this new hybrid drivetrain made its debut at Unbound.
Allied’s Prototypes: A new ABLE or ECHO?
Allied athletes piloted two prototype gravel bikes at Unbound – Payson McElveen in the 200-mile event and Taylor Lideen at the monstrous 350-mile Unbound XL.
The new bikes look long and very slack, with tyre clearance eclipsing anything in the company’s current quiver.
The US carbon manufacturer’s current gravel bike, the ABLE – which took the win in the men’s and women’s Unbound 200 in 2019 – has an elevated driveside chainstay for improved tyre clearance, but is limited to a 43mm tyre out back.
Allied’s all-road model, the ECHO, has a more traditional look, with subtly dropped chainstays and clearance for 40mm-wide tyres.
These new beasts are something else entirely.
The chainstays are very low, tucking the rear wheel close to the seat tube while maximising clearance.
The current ABLE is 1x-specific, but Shimano-sponsored Lideen ran the brand’s new 2x12 GRX Di2 drivetrain, suggesting broadening compatibility here.
However, the Unbound XL racer also opted for slightly narrower 700c x 50mm Vittoria Dry treads.
It’s possible that tyre choice dictates front-derailleur compatibility. Given Allied’s in-house manufacturing capabilities, it’s also possible these are different prototypes.
…and even more new bikes
Heaps of new and unreleased bikes were on show at Unbound and they share some common trends.
First off, if you’re launching a gravel bike in 2024 that can’t fit a 50mm-wide tyre, you are clearly off the back.
Likewise, aerodynamics matters a great deal over the course of a 200-mile race. We’re seeing more gravel rigs with integrated routing and aero cockpits carried over from brands' road bikes to the dirt.
Compatibility with SRAM’s Universal Derailleur Hanger is also key.
A new Giant Revolt?
Giant rider Brendan 'Trekky' Johnston raced aboard what looks to be the next iteration of the Giant Revolt.
Details are scarce, but it appears it’s on-trend – with a new aero-handlebar, internal routing from the bar to the frame, down tube storage and a very compliant seatpost (which looks to be borrowed from the new-ish Defy).
The next Checkpoint?
Trek rider Paige Onweller was on what looks like a new Trek Checkpoint at Unbound.
The bike features an integrated bar/stem combo with plenty of flare in the drops.
The frame lines appear to borrow from the Domane and there’s the addition of a UDH. The vibration-damping IsoSpeed decoupler located at the junction of the top tube and seat tube appears to carry over.
Ridley’s next racer?
Ridley athletes Piotr Havik, Annabel Fisher and Toby Perry were spotted riding a likely successor to Ridley’s Kanzo Fast.
We can’t glean much from the images we saw, but it appears to have an aero frame profile, possibly inspired by the brand’s Falcn RS aero road bike.
Tyre clearance appears to be improved over the previous generation as well.
Suspension setups
Suspension is nothing new to cobbles or gravel. In 2006, Ted King won Unbound aboard a Cannondale Slate with a Lefty suspension fork. Many riders have run Lauf’s leaf-spring forks, suspension stems from RedShift, or the Future-Shock equipped Specialised Diverge – all in attempts to take the edge off Unbound’s rocky roads.
This year, we saw many pros racing suspension forks from RockShox and Fox.
Santa Cruz HT Squad racers opted to swap the carbon forks on their Stigmatas for RockShox Rudys.
The weight and aero penalty of a gravel suspension fork might not be the right choice for every race, but it’s good riders now have the option.
It’s possible this year’s larger pro field made it easier to take advantage of riding in a draft, thereby reducing the drag of these forks’ larger-diameter stanchions.
That said, as popular as the suspension was at Unbound, the men’s and women’s races were won by traditional gravel bikes with rigid carbon forks.
The second-place female finisher, Geerike Schreurs, was the highest-placing rider to use a suspended bike – the Specialized Diverge STR.
Aero takeover
Making fun of marginal aero gains touted in marketing literature is fair game, but saving a few watts adds up quickly – especially as distances increase.
So, it’s no surprise gravel frames, cockpits, helmets and even clothing are becoming increasingly popular.
Rapha’s ‘Blaerosuit’ (bladder, aero, skinsuit) made its debut at Unbound.
The notion of an aero skinsuit with a sleeve for an integrated two-litre hydration bladder might have sounded like an April Fool’s gag a few years ago, but the proof was in the podium, as Morton wore it to a first-place finish.
According to Rapha, the Blaerosuit won’t be available to purchase for now. However, it intends to develop the concept, with plans to launch a consumer-ready version in the future.
Apparel company Rule 28 has developed a similar skinsuit with an integrated 1.5-litre bladder.
Rule 28 partnered with athlete-turned-YouTuber Dylan Johnson to test the aerodynamics of a skinsuit with a hydration bladder, and the brand’s recently launched Gravel Skinsuit is the result.
If a full skinsuit isn’t your thing, Castelli’s hydration-ready Unlimited Pro Jersey also features a hydration sleeve.
The spirit of gravel is alive and well
If all of this cutting-edge gravel technology seems a bit much, please know that the spirit of gravel is still alive and well at Unbound.
Imagine working for – or owning – a bike brand, and rather than racing your bikes at the largest gravel race in the world, you purchase a trio of $200 beach cruisers from Walmart and ride them for 200 miles.
That’s what a trio of riders from Rodeo Labs did this year.
They bought, disassembled, reassembled and customised these coaster-brake-equipped singlespeeds with necessary gravel gear, such as 'sick fades', front baskets, horns and power meters.
Fans gleefully followed their journey on social media and were overjoyed when all three of them crossed the finish line. Please let there be a cruiser class at Unbound next year.
