3T is an Italian brand that has been building lightweight racing components since 1961. They started out by specializing in aerospace grade alloys and of course, nowadays most of their top of the line products are all carbon fiber/composite. We had the chance to get a close-up look at their all new Exploro carbon gravel bike which is available with two distinct build options. This bike can be built up for 700c gravel tires but it can also fit 27.5×2.1″ mountain bike tires.
Watch this video for a quick view of some of the feature highlights of the all new Exploro from 3T Cycling:
3T uses a technology they call “Sqaero” which refers to the squared-off aero shapes of the frames tubes, primarily the downtube which is 50mm wide and is designed to pick up the air flow coming off a wider cross or mountain bike tire and lead the air on to the water bottles. The seattube is 25mm wide to make it aerodynamically “disappear” in between the bottles and the rear tire. The headtube, seatstays and custom seatpost also use Sqaero shapes.
It might seem odd to make an aerodynamic gravel bike, but 3T set out to make the “world’s fastest, most capable gravel bike”. One of the names behind the Exploro might sound familiar too. Gerard Vroomen helped design many aspects of the Exploro and if his name sounds familiar, it should. He is one of the original founders of Cervélo and is now a co-owner of 3T. Vroomen explains, “If we were just about stiffness we would go with a square down tube (stiff, strong, light) but not aero at all. On the flip side, full aero designs are fast, but the stiffness, strength and weight are not as good. We found that if you run a big wide knobby tire in front, it makes the air flow very messy and so you need a pretty wide down tube to counter that by making creating an air foil with the downtube.”
Vroomen continues, “We use what we call our Sqaero technology – the front half is aero shaped, then we square off the tail (which has been done before), but when combined with the 50mm wide downtube (needed because the tires are so wide), we then have a really nice shape for the air flow. So the result is that we have about 90% of the aerodynamic performance because you trick the air flow into following the shape even though the tail is missing.”
When it comes to aerodynamics, factors can be measured in a wind tunnel to test all of the modeling. The testing done on computers can be difficult because of the rotating knobby tire.
Vroomen says, “We tested the Exploro against a test mule with the same size tube but with a round shape. Same geometry and same parts, even the same monostay. The only difference was the tube shapes. We didn’t test with a mannequin which gives you more accurate results (maybe 10 to 20 percent more) but we knew that most of what we were testing was happening between the front wheel and the downtube so the rider doesn’t have a big influence on that area of the bike. It also speeds up the whole testing process by not using the mannequin. And obviously, knobby tires are not as aero as a road tire. The difference is about 7 watts at 20 miles per hour.”
3T tested at 20 mph instead of the more standard 30mph because average speeds for most gravel riders and racers are lower than compared to pure road riders and racers. How thorough was 3T with their wind tunnel testing? Vroomen describes the process, “Even for testing, we did 3-D printed fake mud to emulate real mud (because scientists will frown when you try and bring real mud into their sterile testing centers). This allows us to keep the same mud pattern for multiple tests or tests done at later times. What did we find? Mud has very little to no difference as far as aerodynamics is concerned. And of course, we tested with and without water bottles.”
The Exploro LTD frame weighs in at 950 grams which is light for a disc brake frame. It’s lighter still when you consider that it is an aero disc brake frame and lighter again when you consider that it is a disc brake aero frame that can fit a mountain bike tire. The geometry provides the rider with a good endurance oriented riding position and the chainstays of the Exploro are uber short at 415mm, while still providing plenty of tire clearance.
The Exploro from 3T is available in two versions. The Exploro Team has a frame weight of 950 grams (claimed) and has an MSRP of $3000 for the frameset. The Exploro LTD (featured here) has a frame weight of 1150 grams (claimed) and an MSRP of $4200. Large frames are available now and SM, MD and XL will be available next month (August).