3t Primo 2 Wpnt GRX

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…