• Motorized version of 3T’s Exploro Racemax aero gravel bike
  • Frame comes out of the same mold as the nonmotorized version
  • eBikemotion X35 hub motor system assists up to 20mph (USA)
  • 250Wh internal battery

Price: $10,000 (Dropbar Ultralight), $7,000 (Dropbar), $7,000 (Flatbar)
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[Hello readers. The plan was to have a full review of this bike ready for you to read today. Unfortunately, Covid-related shipping challenges intervened and my test sample is not here yet. I'll post a full review once I get enough time on the bike.]

3T just dropped a motorized version of its speedy gravel bike. The Exploro Racemax Boost is the company’s first e-bike and, unlike most e-bikes that are designed to be solely e-bikes, is basically a motorized version of the company’s already-existing nonmotorized Exploro Racemax. In fact, other than adding a small port in the top tube for the on/off switch and routing some additional wires, it’s the same frame.

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That’s because the Racemax’s sizeable down tube had room enough to fit a 250Wh internal battery, and 3T chose the lightweight eBikemotion x35 rear hub motor. Put a motorized and nonmotorized Exploro Racemax side by side and you’ll need to look carefully to tell them apart.

3t exploro racemax boost
3T made the Racemax into an e-bike with minimal changes.

The X35 hub motor puts out up to 40Nm of torque and assists up to 20mph. A single lighted button in the top tube lets the user flip through three preset—and 3T-customized—assist modes. The user can alter the assist modes by downloading the eBikemotion app and pairing it to the bike. The app is not required to ride the bike, but it does give the rider more information and custom options.

While the X35 doesn’t win the torque wars—it puts out less than half of the 90Nm offered by the Specialized Turbo motor—it has several compelling features. It is very quiet, it fits into a mostly normal-looking frame, it has 2x drivetrain compatibility, bikes equipped with it have regular cranks (and therefore normal q-factors), and it’s light.

3t exploro racemax boost
The Racemax Boost Ultralight weighs just 24 pounds.

That last point is punctuated by the Exploro Racemax Boost Ultralight, which weighs only 10.89Kg, or right about 24 pounds. Price on that bike is $10,000. This bike gets some extremely trick parts to reach that weight, including 3T’s Torno carbon crank, a Carbon Ti front hub, and Carbon Ti’s X-Rotors with steel braking surface and carbon carriers.

3t exploro racemax boost flatbar
The Racemax Boost comes with either a drop or flat bar.

The standard Racemax Boost comes in two options: flat bar and drop bar, both of which cost $7,000. Other than the bar and shift/brake controls, the build is the same: a 1x Shimano GRX 11-speed drivetrain, GRX disc brakes, a 3T Discus 45|40 wheelset with carbon rims, 35mm Pirelli Cinturato Gravel M tires, a Selle Italia Novus saddle, and a 3T bar, stem, and seatpost.

3t exploro racemax boost geometry
Geometry is the same as the nonmotorized Exploro Racemax
Headshot of Matt Phillips
Matt Phillips
Senior Test Editor, Bicycling

A gear editor for his entire career, Matt’s journey to becoming a leading cycling tech journalist started in 1995, and he’s been at it ever since; likely riding more cycling equipment than anyone on the planet along the way. Previous to his time with Bicycling, Matt worked in bike shops as a service manager, mechanic, and sales person. Based in Durango, Colorado, he enjoys riding and testing any and all kinds of bikes, so you’re just as likely to see him on a road bike dressed in Lycra at a Tuesday night worlds ride as you are to find him dressed in a full face helmet and pads riding a bike park on an enduro bike. He doesn’t race often, but he’s game for anything; having entered road races, criteriums, trials competitions, dual slalom, downhill races, enduros, stage races, short track, time trials, and gran fondos. Next up on his to-do list: a multi day bikepacking trip, and an e-bike race.