The Pinarello GAN S is a workhorse of a bike. It comes, with the addition of Easy-Fit, in fourteen sizes, fitting everyone from the small to the tall. The frame design is also similarly wide-ranging, taking its cues from the Dogma F8 and nearly identical to the GAN, GAN RS, and GAN Disk.
Pinarello starts with the Dogma when designing the GAN series bikes. The S takes the shaping and geometry of the F8 and builds it with Torayca T700 Carbon Fiber. The lower-modulus mix is more durable. But to get to the same stiffness, Pinarello needed more material. The resulting generous cost savings means a little added weight.
More importantly, the frame is shaped like the F8. You can see it in the extended head tube, the way the fork crown nestles in a notch in the down tube, the aero fork legs, the FlatBack down and seat tubes and the shorter, lower seat stays. And includes the aero carbon-fiber seatpost. The shaping also owes to the need to make the bike stiff and comfortable. A problem with traditional airfoil tube shaping is that they make a bike vertically stiff and laterally compliant, the reverse of what people need. By shortening the profile of the down and seat tubes, which Pinarello calls FlatBack profile, they still have vertical give. And by cutting the tubes off at their wide point, there is still plenty of lateral stiffness to fight pedal forces. And this is before we get into Pinarello’s traditional asymmetric tube designs, where they have already built in resisting pedaling forces.