Seatpost slippage during a ride is one of those problems you solve exactly once before keeping a spare wedge in your parts bin. The F Series Seatpost Wedge from Pinarello handles the clamping duties on F Series and X Series frames, sitting inside the seat tube junction where it presses against the back of the post when you tighten the grub screw. No external clamp visible, no ring around the seat tube—just a clean transition from top tube to seatpost that contributes to the frame's aero profile.

The wedge mechanism works through compression rather than circumferential squeeze. When you thread the grub screw in, the aluminum wedge gets forced against the seatpost, pinning it in place within the seat tube. This hidden approach shaves 36 grams compared to Pinarello's previous external clamp design while keeping the visual lines uninterrupted. The tradeoff is that saddle height adjustments take slightly more effort—you're loosening a screw that's harder to reach than a quick-release collar.

If you're working on an F5, F7, F9, or any of the X Series bikes, this is the correct replacement wedge. It also fits the Nytro E-Road, Nytro Gravel, Nytro Allroad, and Crossista F models that share the same seat tube architecture. The machined aluminum construction handles repeated installation cycles without deforming, which matters if you travel with your bike and remove the seatpost for packing.... Read More