Italy’s 3T has expanded its Exploro off-road range with the new Ultra, which it is calling the “most extreme aero gravel bike yet” with optimisation for wider tyres. A wider downtube and new fork leg spacing are designed to redirect the airflow coming off a large front gravel tyre.
3T’s performance gravel bike is the Racemax, which fits tyres from 35mm up to a whopping 61mm, but aerodynamically it performs best with 35 to 42mm tyres. While this is great for the rougher tarmac and many gravel roads, 3T recognises some riders may want more on a regular basis, and notes there are three main reasons for this (in their own words):
“These are all valid reasons, and they don't mean you don't like speed,” says 3T. “They just mean you want speed on your terms and are not willing to size down your tyres for it.”
To cater for these riders, 3T is bringing out the Ultra which also fits tyres from 35 to 61mm WAM (width as measured) but is optimised for the upper end of that spectrum.
“For example, the downtube neck that redirects the airflow coming off the front tyre is wider on the Ultra than on the Racemax,” says 3T. Other revisions include a slightly tuned geometry and an interesting seat tube design.
The seat tube is aero like the Racemax and also borrows the rear wheel cutout; but not only is this cutout bigger to accommodate bigger 700c tyres, 3T says it has another trick: “While the outside is aero, the inside is round, so it fits a standard seatpost, giving you the option to run a standard, dropper or suspension seatpost.
“We're not suggesting you run a dropper to win Milan-San Remo, but you could put it to excellent use on tricky terrain to keep better control over your bike.”
The Ultra doesn’t get full suspension as 3T reckons adding suspension risks turning a gravel bike into a bad mountain bike. “If the stuff you ride requires suspension, you may as well ride a good mountain bike,” says 3T. “If it doesn't, then just keep it fast, light and efficient.
“Remember how we want to keep gravel fun?,” 3T asks. “That means we need speed on paved roads - adding weight and complexity through suspension doesn't help that.
“The off-road stuff is fun regardless, no need to add suspension for fun.”
That said, 3T says it has a “hyper-efficient, super-proprietary, multi-linkage system that adds comfort and grip to the bike”. They’re talking about the tyres…
“Once you run something up to a 61mm tyre on the Ultra, those tyres give you a ton of suspension,” says 3T. “Going from a 40mm or even 50mm tyre to a 61mm tyre is a game changer, and it's not just to add comfort, the grip of such a massive tire is also, well, massive; meaning you'll ride more and walk less on even the toughest terrain, and that helps again with the fun factor.”
The Ultra gives you the option between a wide 700c tyre or an even wider 650b tyre.
“In theory, you could design a bike for just 700c and just make the tyres bigger and bigger. Why not 700x61c, or at least 700x55c or 700x50c?”
3T explains: “The problem is, those tyres are big, really big. Not a problem on a mountain bike, which has a long front-centre, a long chainstay and tons of clearance for all the moving parts and for your toes (which ideally has space to move as well), but a gravel bike needs a much shorter geometry to be agile and fun on all surfaces.
“700x50c tyres simply don't fit inside such a geometry, you'll need to compromise with something halfway towards a mountain bike. Going to 650b on the other hand will give you a tyre that - despite being labelled differently - actually has a size that is very similar to all the 700c road tyres that good road geometries have been based on for over a century.”
3T says its 700c tyre width tops out at around 46mm WAM for the Ultra.
The brand goes through its recommended tyres for the Exploro Ultra using its WAM (Width As Measured) and RAM (Radius As Measured) system over here.