The Pinarello Dogma K10S Disk Frameset, takes the endurance frame of the K10, the preferred race bike for the cobbled classics, and adds a shock between the seatstays and the frame. This little feature doesn’t change the geometry of the bike at all; it compresses and bounces back thanks to the adjustable elastomer inside, further damping the rough roads. This is the bike Team Sky took to Paris-Roubaix. They needed the aerodynamics of their Dogma F10, the stability and tire clearance of the K10, and the extra, back-saving comfort of the shock to have an edge. It worked. Their man Gianni Moscon finished fifth in the 2017 Hell of the North.

The shock is small, but important. It allows for up to 10mm of compression, and has an adjustable pre-load. When the shock was first installed on their K8-S, tests found the frame 4.6% more compliant, but speed was eight percent higher on cobbles, with ten percent less effort. There is a standard elastomer that comes in the shock—it and the shock are designed to work with people weighing up to 90kg. Those on the light end of the adult weight spectrum, under 50kg or so, might want to get a softer-durometer elastomer, available as an after-market accessory. The frame is also designed to work with an electronic version of the shock, one that sits in the seat post, is wired to the shock, and is equipped with a “brain” that possesses an accelerometer, a gyroscope, and programming to adjust the shock on the fly. It’s adjustable via a wireless remote. From rigid on smooth roads to fully active on rough roads. It’s available via special order, and works only with the current generation of K10S frames.

The shock is the proverbial icing on the cake that the K10 is. It was derived from the Dogma F10, and Pinarello changed the geometry work in two distinct ways. First, they’ve lengthened the wheelbase by both moving the front wheel forward and the rear wheel back relative to the bottom bracket, which retains the 72mm drop across most sizes. The longer front center comes with a shallower head angle by about a half a degree and 4mm more fork rake and 6mm more total fork length. This increases trail and stability. The seat angles remain the same in the same sizes as the F10, to give you the same position relative to the bottom bracket. The seatstays have been lengthened by 9mm across most frame sizes, which adds comfort.

In terms of comfort, Pinarello also shaped the chain stays to be flatter vertically, which they call “Flexstays” for better vertical compliance, and the seatstays have been shaped into a fork-like curve for even more bump damping. The extra length in back and front also gives riders room to install tires up to 28mm in width. The seatpost is scalloped in back to allow for some rearward flex, further damping whatever road vibrations make it to the frame.

The geometry thus defined, we can now focus on the frame shaping. And in this area, the K10S unabashedly steals from the F10. Pinarello thought the aerodynamics of the F8 were good, but needed to be better in a few places. Most notably, making sure the bike was more aero with two bottles sitting in the main triangle. Improving the airflow around the bottles was the most important key to reducing drag. You’ll notice that the fork crown still nestles in a notch between the down and head tubes. And if you take a look at the fork tips, you’ll see extended material behind the tips. These are “fork flaps” in Pinarello jargon, and they smooth out airflow on the trailing edge of the tips. Below the fork, the down tube dramatically changes shape just where the top of the down tube bottle rests. The new shape shields not only the down tube bottle, but the seat tube bottle if it’s run on the lower mounting point (there are three bosses in the seat tube, use the lower two for this aero advantage). The result of the shaping work is that the area around the bottles is 12.6% more aerodynamic. Less dramatic but still important is the shaping around the head tube and the underside of the top tube. These are designed to smooth flow as well.

Pinarello is also known for their asymmetric designs. For them, that means slightly off-setting and re-shaping frame tubes so the frame is better able to resist torsional forces created by pedaling. The results are subtle enough not to see in pictures, but are obvious to the eye in person. The down tube is offset to the right, while the seat tube offset to the right, and even the stays are moved in that direction as well. Visually, the asymmetry of the seat stay yoke is surprising, but elegantly subtle.

Aero bikes often lack lateral stiffness. The shaping often places material in the wrong places to maximize the rigidity in this plane—the traditional teardrop shape is usually to narrow side-to-side. Pinarello actually made the F10 stiffer than the F9. The tapered 1 1/8” to 1 ½” steered increases lateral stiffness at the fork. The improved shaping and new asymmetries increase lateral stiffness at the bottom bracket. The result is 7% stiffer overall.

Pinarello keeps the frame aero by running cables, housing, wiring internally. If you run Shimano’s latest Di2, your E-Link can be accessible through a port in the down tube above the bottle—no need for a mount under your stem. All the necessary stops and plugs are included. The battery, if you go electronic with Di2 or Campagnolo EPS, goes in the seatpost.

The included aero flex seatpost itself is 350mm long, with a 25mm setback. The saddle clamp can work with oval or round rails—make sure to heed the torque rating marked on the post. The post is secured to the frame as aerodynamically as possible, with two bolts behind the seat tube, called Twin Force Closure.

The frameset comes with tapered 1 1/8” to 1 ½” headset, top cap and spacers. There are round and aero options. In both cases, there’s a 15mm top cap, two 10mm spacers, and one 5mm spacer. The aero option is designed to work with Pinarello’s MoST stem and/or integrated bar/stem combo. The bottom bracket is Italian threaded.

The Pinarello K10S is an aero race bike that has the geometry to enjoy rough roads and a shock to tame Paris-Roubaix.