3T Primo 2 WPNT GRX Bike

The 3T Primo 2 WPNT GRX Bike starts where most gravel bikes stop — at the wind tunnel. 3T's REALFAST aerodynamics program isn't built around tire manufacturers' stated dimensions. It's built around actual measurements: WAM (Width As Measured) and RAM (Radius As Measured), the numbers you get when you mount a tire on a rim, inflate it to pressure, and measure what it actually becomes. Those numbers drove the shape of the frame. That precision is the difference between a bike designed around a spec sheet and one designed around reality.

The Sqaero downtube is the REALFAST story made physical. At 50×75 mm with a truncated airfoil profile, it's sized to guide airflow around the wide front tire. Starting from 50 mm means a traditional full airfoil would need to extend 150–200 mm to maintain flow — creating more surface drag than it saves. The truncated Sqaero profile avoids that tradeoff entirely, and 3T extends it across the whole bike: head tube, fork legs, seatpost, and seat stays all carry the same airfoil logic. The bottles on the downtube sit in the wake of the frame, shielded from airflow when you're riding in the drops. 3T tested the Primo² at both 30 mph — the wind tunnel standard for road bikes — and at 20 mph, which better reflects actual gravel and mixed-terrain riding speeds. That dual-speed approach acknowledges what most aero engineering ignores: you spend more time at 20 mph than 30 on gravel.

The Primo² sits differently in the 3T lineup than the RaceMax or the Extrema. Those bikes lean into pure gravel geometry — lower, longer, built for race pace on rough terrain. The Primo² takes a more road-inspired stance: taller stack, shorter reach, and handling that carries confidently across tarmac and dirt alike. It accommodates 700×46mm tires with 4 mm clearance to every frame surface, or drops to 650b when you want more cushion on rougher routes. The drive-side chainstay drops to improve clearance between the tire and the 40T ring — a practical detail when you're running wide rubber close to the drivetrain. The threaded bottom bracket eliminates the creak risk that press-fit systems introduce in carbon frames. No alloy rings bonded into the shell, no added complexity, and significantly better long-term reliability. The 3T APTO semi-integrated stem manages cable routing cleanly while remaining compatible with both 1x and 2x mechanical groupsets alongside electronic options.

The GRX build pairs Shimano's gravel-specific groupset with the Primo² chassis in a way that makes sense for how this bike actually gets ridden. The RX822 rear derailleur and RX610 shifters deliver crisp, confident indexing across terrain that would rattle a road groupset into imprecision. The 40T chainring combined with the Shimano Deore M6100 10–51 cassette gives you enough range to climb loose, technical grades and recover that speed on the road sections between. RX400 hydraulic disc brakes with 160mm Shimano RT64 rotors stop cleanly in wet and muddy conditions, which matters when the day's conditions change. Fulcrum Rapid Red 900 or Fulcrum Racing 600 wheels roll under the frame as a reliable, compliant platform, ready to run the Pirelli Cinturato Adventure 700×45 or Vittoria Terreno T30 Sport 700×40 tires the bike ships with.

The WPNT designation means every frame is painted at 3T's factory in Presezzo, Italy — not outsourced, but done in-house as part of the manufacturing process. The Primo² comes in four colors: Gesso (white), Orchidea (lavender), Fumo (smoke), and Salvia (sage). These are original graphics developed by 3T's design team using premium paints selected to reflect each bike's character. For a bike this technically considered, it's appropriate that the finish receives the same attention as the carbon layup. The Primo² GRX fits the rider who wants one bike capable of a fast group road ride in the morning and a gravel adventure in the afternoon — without feeling like a compromise in either direction.