The Colnago Concept Aero Disc Road Bike takes it's name from the project that began a carbon road bike project back in 1986, when Ernesto Colnago and Enzo Ferrari began to develop what was to become the revolutionary C40.
Sharing the ethos of that project 30 years ago, the new Concept has been designed to be as fast as possible, to take the now commonplace aero road frame and make it faster still and to offer the rider every advantage of speed whilst maintaing superb ride characteristics and efficiency.
As with all bikes with aerodynamic qualities, the front of the bike needs careful consideration as the air-flow at the front directly affects the overall aerodynamic result. In order to minimise drag from the outset, the three elements of fork, headtube and handlebar were critically examined. The Concept shares a similar fork to the V2-r, in that the leg shapes are very much the same, however, the Concept employs a greater degree of spacing around the wheel/tyre (so much so that it is possible to use 28mm tyres) and -like many others - uses NACA profile tubes to optimise the airflow in wind tunnel tests. In addition to the NACA profiling, the Colnago Concept has also undergone rigorous 'real-world' testing to ensure that the forks perform in a wide range of angles and at speeds encountered in race conditions. Designed as an integrated element of the frame, the fork sits tightly within the frame but unlike others leaves a 'hole' behind the crown in order to allow disrupted air from the counter-rotating front wheel to develop into a small turbulence that has no effect on the aerodynamic efficiency of the down-tube.
The headtube has also been modified from a circular shape and has its basis in NACA profiling. No part of the headtube is round and this has increased the smoothness of the airflow over this critical area. Not wanting to compromise on bike handling and ride feel (as has historically been the case with aero frames) Colnago ensured that the stiffness of the headtube - a fundamental element of the handling of any bike - was maintained with the use of a tapered 1-1/8" to 1-1/4" headset. Subsequently, as a result of the oversized nature of the lower bearing, Colnago built the the downtube close to the profile limits allowed by the UCI. Like the Pinarello F10, the aero shaping of the headtube also led to a dedicated headset and in this instance is also NACA profiled for optimal aerodynamics.
The development of the front end is not all external. As previously mentioned, aero design can often result in a more harsh ride feel and since the ability to maintain an aero position is in at least part down to rider comfort, Colnago decided to engineer some comfort back into the bike at the front end. Stiff headtubes and fork assemblies transfer vibration more directly to the rider, the Colnago Concept counters the problem with a unique approach to headset design. In the first instance, Colnago altered the lamination process of the fork steerer in order to reduce vertical vibration transmission but more importantly, they developed a headset that has built-in vibration cancelling qualities. The clever use of a carbon and polymer proprietary cup design, which incorporates nylon and elastomers, creates a headset that has inherent damping qualities and which results in greater comfort and handling. As an additional benefit, the headset is better sealed than many and this should help reduce maintenance intervals.
Further to the oversized profile of the downtube which is important both in terms of energy transmission and aerodynamics, Colnago performed several studies in the wind tunnel to address the specific nuances of tube shape when coupled with water bottles. Their studies revealed that a broader tube lower down the bike, when accompanied by a water bottle, is more aerodynamic than a continuously slimmer tube. Consequently - and no doubt a development of their TAP truncated Aero Profiles as found on the V2-r - the Concept features a flatter section towards the base of the downtube with an additional hole drilled for a lower water bottle mounting - which further enhances aerodynamic efficiency.
Cable routing is entirely internal as you might expect when optimising air flow. The difference with the Concept is that the routing is very clean where it enters the frame and is not bunched-up causing line issues and inadvertent cable crimping which subsequently affects shifting and braking performance. While this may seem trifling, we have seen bikes recalled for this reason and discontinued just months after their release to market.
As you might expect, the Concept employs Colnago's proprietary ThreadFit 82.5 bottom bracket as found on the C64 and V2-r. Offering improved stiffness, service life and with no impact on tube thickness (and therefore weight) the TF82.5 system is compatible with all PF86 bottom brackets and its wider BB shell lends superior power transfer for maximum performance advantage.
The seattube of any bike plays a specific role in both the aerodynamics and comfort/handling characteristics. These two elements are often juxtaposed, a more aero tube detracting from the ride feel and vice versa. In order to balance the individual requirements on the Concept, Colnago have used a tube that tapers to the width of the bottom bracket - an area that sees relatively little airflow - in order to maximise stiffness and power transfer and which narrows, following a specific cut-out shape around the rear wheel to minimise aerodynamic drag. The low mounted stays improve comfort while dramatically reducing the turbulent airflow around this aerodynamically critical area. The seat tube uses a traditional foil shape truncated with TAP shaping and the construction allows the use of 25mm tyres. On the Rim brake equipped models, despite the optimal aerodynamic positioning of the brakes being direct mounted on the bottom bracket, Colnago have chosen to mount the Direct Mount brakes on the seat stays of the Concept as a result of feedback from Pro teams. The argument here is that it allows for easier maintenance and critically, faster wheel changes - aero gains made with BB mounted brakes can easily be undone with a poor wheel change. For these Disc ready models, Colnago employ the (almost) standard flat mount disc brake caliper mounts and their proprietary HEX12 thru-axle design for use with all 100x12 (front) and142x12 (rear) wheels. The thru-axle conveys greater stiffness to the frame and is less susceptible to flex and wheel-shift under high torsional braking loads than a traditional quick release system.
Like the C64, the Concept is 'designed to size' to offer the same handling characteristics and aerodynamic benefits to riders of all sizes. The Concept is 100% UCI legal in every size and the differing design from size to size is most evident at the seat-stay / seat tube junction. Smaller sizes have a closed junction while larger sizes use a progressively more open design to further reap aerodynamic reward through improved airflow - not possible on smaller frames.
As mentioned earlier, it is possible to run 28mm tyres in the Concept. This allows the Concept to be more of an all-round bike should the rider want it to be their go-to regardless of the type of riding. This tyre width includes an additional 4mm of clearance on each axis for proper clearance and, after extensive wind-tunnel testing - it has been verified that the aerodynamic drag from their use is negligable when compared to a 25mm tyre. This is largely thanks to the already wide design of the seat tube and its truncated shaping which helps shield the rear wheel.
As befits a ground-up design, Colnago spent considerable resources in developing a stem interface that would convey even greater power savings to the rider. The R41 aero stem is a ground-up, full carbon construction that eliminates the limited options of an all-in-one integrated bar-stem while simultaneously optimising airflow over the front of the bike. Available in 5 lengths from 90 to 130mm, the aero stem has no forward facing mounting hardware and will accept most 31.8mm handlebars currently available. In addition, having studied the stem interface in the wind tunnel, Colnago also developed AeroCovers for the area directly outside of the bar clamp to further reduce drag. If you want the benefits of this design in numeric terms, Colnago claim a 2 watt saving at 50kph (30mph) compared with an average integrated system and 6.6 watts versus a traditional round bar and stem - a significant gain. The bike itself - when partnered with what Colnago refer to as a 'medium sized rider' - is aerodynamically superior to the frames developed at the same time : the C60 to the tune of 20 Watts, and it knocks 4 watts off the performance of the V1-r at a 0oyaw angle.
Ultimately the Concept is slightly less stiff at the front end (though marginally more so at the rear) than both the C60 and V1-r but the obvious aero benefits are the big selling point here and the comfort, though over half as compliant as both, is not so punishing as to be unrideable over distance, particularly if partnered with a 28mm tyre.
The Concept is available in 6 colours: 2 Art Decor and 4 standard.