A US patent applied for by Specialized has revealed a radical new design for a road bike suspension seatpost.
The patent drawings, discovered by BikeRadar, show a damper mounted in the top tube that allows the seatpost to move between two positions.
The description accompanying the drawings reads: “The damping member (e.g., a hydraulic damper) couples the seatpost to the frame to dampen movement of the upper portion of the seatpost between the first and second positions. A collar can be used to secure the damping member to the seatpost. The damping member can be positioned at least partially in a tube of the frame, such as the top tube. Preferably, a lower portion of the seatpost is substantially rigidly secured to the frame, and the seatpost flexes when the upper portion of the seatpost moves from the first position to the second position.”
An exploded diagram illustrates the position of an “oil filled through shaft damper with a low speed rebound adjuster” inside the top tube. Covering the gap between seatpost and seat tube that the system would create is “a resilient boot positioned to cover the top opening of the seat tube… made from a suitable elastomeric material, such as silicone.” This would prevent dirt and water ingress.
Specialized supplies more than one embodiment for tuning the system: one is by offfering seatposts with different amounts of flex while another is to fill the gap with “a resilient bushing to provide extra support to the seatpost and resistance to flexing. In this embodiment, in the event that a rider perceives that the seatpost is flexing too little or too much, the bushing can be replaced with a softer or stiffer bushing to achieve the desired amount of flexing.”
The drawings show a very long seatpost clamped inside a flared seat tube just above the front derailleur clamp, which would supply the required flex along its length as well as the strength.
The current Roubaix features Specialized’s Future Shock 2.0 damper, which supplies 20mm of travel above the head tube via a spring.
Although the patents do not name the Roubaix model, it seems like the most likely bike to benefit from rear suspension. Already Pinarello uses rear damping with the Dogma FS, while Trek has the IsoSpeed decoupler-equipped Domane.
However, it is equally possible that Specialized’s new tech is headed for a gravel bike such as the Diverge. The patent was submitted back in 2018, so there’s every chance that it was part of a design that was later cast aside – though some bikes are several years in the making (the Ares shoes took a reported three years!)
In a statement, the brand said: “Specialized’s team of obsessive, driven engineers and designers are constantly developing concepts and technology to improve riders’ experiences – a great example of our Innovate or Die philosophy. Some of these ideas eventually turn into products riders can buy and enjoy, while others remain just part of the development process.”