The 3T Exploro Ultra is a gravel bike released earlier this year and is the third Exploro to be designed by Gerard Vroomen and manufactured by 3T, although it should more accurately be labeled as a counterpart to the 3T Exploro Racemax.

The Exploro Ultra uses a 3T frame design which 3T claims is aerodynamically optimized around 650B tires in the 55-61mm range.

The 3T Exploro Ultra Crank Brothers Edition costs £8,699 and sits at the top of a four-bike range.

While the bike is an extreme example of trying to blend in seemingly disparate genres of riding, Vroomen brilliantly harnessed the transformative effect of tire size and pressure.

The Exploro Ultra combines extreme off-road capability with fast on-road driving to create a versatile and distinctive design, although a specification detail or two on this model might be worth reconsidering.

3T Exploro Ultra Development

The Exploro Ultra is technically the third iteration of 3T’s popular but controversial aero gravel bike, but it would be more accurate to say that it’s actually the other side of the coin of the second iteration rather than the other side of the coin. a dedicated third revision.

While both bikes have the same max tire clearance of 61mm x 650B, 3T says where the Exploro Racemax has an aerodynamically optimized frame around 35mm-42mm 700C tires, the Exploro Ultra was designed to work best with 650B tires at the upper end of its clearance capability, around 55mm-61mm.

The two bikes will be side-by-side in the 3T lineup, each aiming to cater to specific niches but partially overlapping.

Since its inception, the Exploro platform has never garnered universal approval, with some questioning the effectiveness of focusing on aerodynamics in a gravel bike, potentially at the expense of other attributes like comfort.

Given that the Ultra’s mission is the most technical and slowest terrain a gravel bike could reasonably be asked to tackle, the argument of those in this camp is likely to be voiced louder than ever. .

Gerard Vroomen, the designer of Exploro, says these people misunderstand the concept of the family of bikes.

“They think the gravel is something separate, rather than related to the road. More often than not, gravel riders have to get out of town into the woods, so to keep this part fun you need to do it fast.

Therefore, Vroomen aims for the aerodynamics of the Exploro bikes to come into play on the road, not necessarily on the gravel. It then relies on the fat tires’ ability to replace the frames’ otherwise aggressive attributes once off-road.

The logic is no different in the Ultra, it’s just optimized around a setup that allows riders to tackle the most extreme gravel terrain.

He believes that trying to maximize comfort with a less drag efficient frame design or the introduction of suspension devices creates such a penalty to speed without a sufficient increase in capability that ultimately the rider has interest in going the Ultra route.

“Adding suspension risks turning a gravel bike into a bad mountain bike. If the things you ride require suspension, you might as well ride a good mountain bike. If not, just keep it fast, light and efficient,” says Vroomen. For what it’s worth, that’s a sentiment I would support.

3T Exploro Ultra frame

With its low-profile fork crown and thin head tube but dramatically flared downtube, the Ultra’s counterpart, the Racemax, is pretty radical when it comes to modern frames.

To help manage the airflow coming from its much wider tires, the Ultra gives the Racemax a relatively vanilla look. The design elements are still there, but their dimensions have been significantly increased.

The Ultra has a new, wider fork and the top of the downtube has increased in width to 60mm, before dropping into a 75mm wide section designed to neatly hide the bike’s water bottles from the air.

3T Exploro Ultra Version

A key change to the Ultra is its seatpost compatibility. While the seat tube externally resembles that of the Racemax, it can now house regular round posts instead of a proprietary aero post.

This creates the ability to specify many aftermarket choices, such as those with additional flex or dropper posts.

Indeed, this Ultra version uses Crank Brothers’ new Highline 11 dropper post. It uses a carbon fiber nib (the part that slides into the post itself) and head, as well as titanium hardware, for a weight of 389g.

It’s an impressive component both visually and in terms of weight, but I think most riders, even those who choose the Exploro Ultra to tackle extreme terrain, would be better served longer or shorter by choosing to use one that improves comfort instead.

Plus, operating the Crank Brothers Highline 11 was no small feat. The lever was stiff and where it was placed on the bars it encroached on the position of my hand in the drops meaning I rubbed the skin of my thumb joint several times with the underside of the lever .

I think overall a dropper doesn’t serve enough people enough time to be worth it.

Although I found the Apto 100mm 3T stem a bit short for me (the reach was brought back into the frame so I’d rather not increase it further by using a shorter stem than usual), elsewhere the construction of the bike is excellent. Most of it is also made by 3T, actually.

The wide flare on the 3T Superghiaia bars offered a nice feeling of control over rough ground, while the 3T Discus i28 wheels felt sturdy and felt wide enough to properly support the 2.1-inch Vittoria Barzo tires, for the bike handled in confidence at supremely low tire pressure.

The mule drivetrain created by 3T’s sleek Torno 1x crankset and Sram’s Eagle XX1 AXS eTap derailleur and 10-50 Eagle cassette were also well chosen, echoing the overall mission of aero performance combined with the rugged capability of the framework in general.

Geometry and sizing 3T Exploro Ultra

Geometrically, the Ultra has been modified from the Racemax. The 419mm chainstays, while still unusually short for such a capable bike, are 4mm longer than those on the Racemax.

This allows for more 700C clearance (46mm versus 42mm on the Racemax) as well as better mud clearance for the larger 650B tires.

Reach has been brought back about 5mm, to move the rider position up and back and balance out the longer rear end.

Driving the 3T Exploro Ultra

The Exploro Ultra is Vroomen’s most over-the-top example to date of how it can successfully fit together in drop bar genres—aero and gravel—that are usually so disparate.

In his designs for 3T and Open, Vroomen leverages the transformative effect of tire size and pressure perhaps better than anyone in the industry.

Because tires have such an influential role in a bike’s handling behavior, the Ultra changes personality as hugely as it mixes genres.

Off-road, those chunky Vittoria tires compensate for the inherent harshness of the bulky aero frame and allowed me to tackle technical terrain with ease.

Yet back on the tarmac, the attributes of the frame became more dominant. I’m not talking about the claimed aero qualities of the frame per se, but the bike definitely feels a lot more like a stiff and fast road bike than its off-road capabilities would otherwise suggest.

Verdict 3T Exploro Ultra

There were a few hiccups in the specs for me personally. The Ultra’s Crankbrothers Highline 11 carbon dropper post is a feat of engineering, but I think most riders would be better served most of the time by swapping out a regular, comfort-enhancing carbon post.

Given the decrease in frame reach, the short 3T Apto stem also exacerbated the feeling of sitting upwind in a normal riding position.

That said, overall I was as happy taking the Ultra on my local roads as I was using it to attempt white-knuckle singletrack.

I don’t think there are many other bikes I could say that about, which is a testament to Vroomen’s ingenuity and 3T’s execution.

Choice of kit

Syncros G4 bottle, MSRP €7.99

The humble water bottle is an often overlooked piece of kit, but one that can be a constant annoyance on a commute if it’s poorly designed.

The G4 water bottle from Syncros has a simple, clean design but does everything right. It has a 600ml capacity in a shape that fits well in a bottle cage and is easy to squeeze despite its sturdiness.

On the business side, its nozzle is comfortable to grip and allows a liberal flow for a given liquid. The closure design is also simple, so it is easy to clean. I’ll take two, please.

Alternatives to 3T Exploro Ultra

3T Exploro Ultra Ekar 650B

The Exploro Ultra Ekar 650B version is £3000 cheaper but still uses quality components. Campagnolo’s accomplished Ekar 13-speed gravel groupset offers a better solution to hitting both range and close gear steps than any other 1× groupset currently on the market.

3T Exploro Racemax Force AXS 1x

The Exploro Racemax Force AXS 1x is around the same price as the Ultra at £6,999, but has been tuned to go fast on medium 700C tires rather than wide 650B tyres. It even uses 3T’s low-profile Torno 1x crankset to reduce drag.

3T Exploro Ultra Specification

Image credits. Detail and riding shots: Lizzie Crabb; geometry chart and alternative bike images: 3T

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