Argon 18 E-117 105

The E-117's carbon frame is built around a triathlon-specific geometry that holds a 78-degree seat tube angle across all five sizes — XS through XL. That steep angle rotates the rider's hips forward relative to a road bike position, reducing the hip angle at the top of the pedal stroke. In triathlon, that matters specifically for the run: a more open hip angle on the bike preserves range of motion in the hip flexors, which translates to a more natural running stride off T2. Chainstays hold at 413mm across all sizes, and the head tube holds at 72 degrees, producing consistent front-end geometry from the smallest to the largest frame. The bike is designed to put riders in an aggressive aero position and keep them there comfortably for the duration of the bike leg.

The fit system that distinguishes the E-117 frame is Argon 18's 3D System. On most tri bikes, handlebar height is adjusted by stacking spacers below the stem — a method that introduces compliance into the steerer and can allow the front end to flex slightly under hard efforts. The 3D System raises the top bearing instead of adding spacers, integrating the head tube extension as a structural component rather than a stack of separate parts. Each frame size supports up to three extension heights, allowing the stack height to be adjusted without any loss of headtube stiffness. Custom 3D…