Co-engineered with Jaguar, the Pinarello Dogma K8-S is the weapon Team Sky used to tackle the cobbles

Product Overview

Overall rating:

Score 9

Pinarello Dogma K8-S

Pros:

  • Traction
  • Comfort
  • Braking
  • Maintenance

Cons:

  • Headset seal problematic
  • Compact chainset
  • Seatpin bolts susceptible to rust

Product:

Pinarello Dogma K8-S

Manufacturer:

Price as reviewed:

£8,799.00

Ever since man first wobbled down an unmade road on a velocipede, bike and equipment manufacturers have been trying to make the two-wheeled form of transport more comfortable.

Saddles with springs, shaped tubing and of course the pneumatic tyre have all been introduced and, to varying extents, stuck around.

Modern adaptations are a little more sophisticated, as are the roads we ride on, but the aim is still to improve the comfort of our ride.

Pinarello has gone about solving the problem by adding an elastomer suspension damper to the top of the seatstays that bolts to the back of the seat tube. When it was launched in 2015 it was, unsurprisingly, during Team Sky’s Spring Classics campaign; a cobble-busting aero bike for the Tour of Flanders and Paris-Roubaix.

While most of us will never tackle the Arenberg Forest (at least not on a £9k bike we’d bought ourselves), is there a need for such technology in our day-to-day riding? We’ll come back to that.

Frame

It may be designed for the cobbles, but at its heart the K8-S is an aerobike

It may be designed for the cobbles, but at its heart the K8-S is an aerobike

Away from the elastomer suspension, this is a standard Pinarello Dogma F8 frame, with all its aerodynamic profiling and top-quality Japanese Torayca carbon.

Design-wise it is largely the brainchild of Dimitris Katsanis, coupled with carbon engineering from Jaguar and Pinarello’s bike-building know-how.

The rear dampener gives 10mm of travel

The rear dampener gives 10mm of travel

But it’s the suspension that really shines. The elastomer (basically a piece of rubber encased in that pod) gives 10mm of travel.

The flex stays further improve comfort

The flex stays further improve comfort

By flattening and widening the chainstays (called Flexstays here) just behind the bottom bracket, the movement in the damper is soaked up to avoid any damaging stresses being placed on the tube junctions (especially at the bottom bracket).

The Flexstays’ width helps maintain the frame’s rigidity.

Specification

Naturally the bike has full Dura Ace Di2

Naturally the bike has full Dura Ace Di2

Shimano Di2 is to be expected on a bike of this price and, as you probably know, works superbly.

A direct-mount rear brake is used, as the damper takes away the mounting space for caliper brakes.

Most is Pinarello's in house brand

Most is Pinarello’s in-house brand

Elsewhere Pinarello has specced its Most bars, stem and own-brand seatpost, all of which do the job without being overly fussy.

The Mavic Ksyrium Elite wheels are light and stiff with superb braking (even in the wet) thanks to the Exalith textured braking surface.

>>> Are wider tyres really faster?

These came with matching Mavic Yksion Pro 25mm tyres that rolled nicely, gripped well and didn’t wear out too quickly.

Ride

Pinarello K8s Suspension05

Suspension and wide tyres give a comfortable ride

The damper, coupled with 25mm tyres, gives a very smooth ride. It’s not like a full-sus mtb where you can feel the bike moving beneath you, but enough to give you the sensation that the road surface is better than it is.

>>> Do riders need a special bike to win Paris-Roubaix? Mathew Hayman didn’t

I still felt the bumps and the potholes but the edge was taken off enough to help my lower back feel less battered and bruised than usual following a five-hour ride.


Video – Geraint Thomas Pinarello Dogma K8-S


Comfort, however, isn’t the main gain with the damper. Traction is. Take this bike on a rough or gravelly road and the suspension keeps the rear tyre firmly on the ground. This improves grip by minimising those split seconds when the rear wheel is unweighted. It means you can keep pedalling without any loss of force.

>>> 13 ways to make your ride to work more like Paris-Roubaix

This traction also helps when descending through rough corners. On a normal, stiff carbon frame you might feel the back wheel just skipping out very slightly.

The Pinarello K8-S soaks these vibrations up, improving grip massively. It was genuinely surprising just how much better planted this bike felt when cornering.

Value

Pinarello Dogma K8s 08_1

Fast back tube profiles have a Kamm tail-like cross section for improved aerodynamics

Of course, a ‘value’ bike this isn’t; you can get two very good bikes for this price. You do, though, have to remember you are getting the very latest in technology, the best groupset on the market and a fantastic bike.

For the type of terrain you are faced with every day in the UK, something like the Pinarello K8-S does make sense, especially against its thoroughbred counterpart, the F8.

Verdict

You’re unlikely to find a ride equal to this. The frame is as light and stiff as anyone could ask for, while the elastomer provides cushioning and traction that you won’t get on any other aero road frame. From crits to long days in the saddle, this bike will do it all and as such will suit those who enjoy big-distance challenge events as well as the racers out there. All great, of course, but there’s one more thing that stands out, and makes the K8-S even more praise-worthy. It is one of the most practical bikes I have ever worked on. Aero bikes, like TT machines, are renowned for fiddly bolts tucked away in hard-to-get-at places, making maintenance a nightmare. Not with the Dogma. Every bolt is easily accessible and adjustments are easy. How many top of the range bikes can you say that about? This was a design brief and they’ve nailed it

Details

Miles ridden:827
Weight:6.95kg / 15.32lb
Size tested:53cm
Sizes available:42 - 62cm
Frame:Dogma
Fork:Onda
Groupset:Shimano Dura Ace Di2
Alterations:52/42 chainset, saddle
Gear ratios:52/42, 11-28
Wheels:Mavic Ksyrium
Tyres:Mavic Yksion Pro
Bar:Most
Stem:Most F-Series (alloy)
Seatpost:Pinarello
Saddle:Selle Italia
Distributor:Yellow Ltd
  • Catflap Jones

    Evidence for these wheels being stiff? They are most certainly not. Possibly because they have been laced the wrong way around but definitely they bend left to right with even modest torque.

  • Ciaran Carroll

    Simon Richardson from GCN?