In 2015 bike manufacturer Pinarello unveiled the K8-S - an aero road bike with rear suspension that was Team Sky's weapon of choice for the cobbled classics.
Team Sky used it to great effect with Ian Stannard winning the Omloop Het Nieuwsblad and Geraint Thomas taking victory in the E3 Harelkebe, breaking the team's WorldTour duck for the early season classics.
So, why has it taken so long for a road bike with suspension to come to the fore in professional racing? Purely from a manufacturer's point of view it has always been difficult to create a frame with enough rigidity to handle the flex created by suspension, especially within the weight limits and specifications of the UCI rulebook.
The K8-S was such an innovation because it was able to do this effectively thanks to modern carbon fibre technology, even though at it's heart it is a standard F8 frame with some modification.
The suspension module itself is a pretty simple elastomer creation - basically a piece of rubber inside a pod - which provides up to 10mm of travel. This has a significant dampening effect on the road, especially over cobbles which the classics are famed for.
The real groundbreaking technology is in Pinarello's 'flexstays'. Pinarello created a chainstay that was wider and flatter than the usual F8 frame that was able to handle the flex in the frame created by the suspension movement - reducing tension on the frame and making suspension road bikes a viable option for pro teams.
So was it a one-off?
Yes and no. The K8-S was one of the first generation of 'active' suspension systems, meaning it has the elastomer dampener which actively moves to absorb the road. But the far more popular kind of suspended road bike has been appearing in the form of carbon fibre manipulation.
This basically means using different grades and amounts of carbon in the manufacturing process in order to create a frame which is more flexible. This 'passive' system of suspension is often coupled with elastomer inserts in the frame which help to reduce 'road buzz' as well as improving the comfort of the ride.
Several bike manufacturers now employ this method for their top level bikes including Specialized, Lapierre and Trek; all with different variants.
The rise in interest in road bike suspension has also given birth to many products that can be bought to upgrade your standard road bike to make it more comfortable - with seatposts and forks being the two main areas these products are focusing on.
So it looks as though suspension road bikes are here to stay, but not in the obvious format of the K8-S - the suspension road bikes we ride in the future are likely to be a little more subtle.
Even then, it seems like it will be a long time before entry level carbon road bikes come with this technology.
