The Definition of Performance

Current ideology within the bike industry has fixated on very narrow definitions of performance, typically isolated to the notions of aerodynamics, stiffness, and weight. We agree that these factors are important to the performance of a bike, but an obsession with making a bike ‘fast’ has meant that frame designers have forgotten what it means to make a bike that’s ‘best’ for the real world.

For such a simple machine, the physics behind cycling are so complex that engineers are still trying to work out the sum of all the parts. Some are easy to measure (weight, stiffness, and so-on). Others are harder to explain:  compliance, character, durability - the factors that combine to produce actual ride quality. Out of genius or laziness (or perhaps both), the marketing teams within major bicycle brands have leveraged this ambiguity and chose to promote the factors that are quantifiable – because who can argue with numbers? Such focus has resulted in the elite race bikes of today sold to customers with bold promises of physics-defying speed and performance.

The reality is that ‘aero’ bikes developed in wind tunnels are uncomfortable and energy sapping,  ultralight bikes are soft and disposable, and that high-performance bikes must have high price tags to match.

 It’s here our design philosophy was born. Fast, durable, comfortable, bikes with honest pricing. Bikes that are aerodynamically optimised but not compromised, bikes that are light weight but durable, bikes that have refined stiffness for driveability but flex for comfort and character. As the old saying goes ‘the best bike is the one you enjoy riding the most’ and that’s what we aim to create.


Aerodynamics - Myth vs Reality

Aerodynamics has become the buzzword for modern bike designs and that’s not entirely a bad thing. Wind tunnel testing and CFD (computational fluid dynamics) have taught us that aerodynamic drag at racing speeds (>50Km/h) equates to 90% of total drag, and as such has sparked an obsession with finding the path of least resistance through the air. Aerodynamically optimised components and frames have deep profiles to help reduce separation of airflow and subsequent turbulence. A common side effect of creating larger, more aerodynamic profiles, is an increase in stiffness – which is often unwelcome and creates problems for frame designers. This increased stiffness along with an aggressive aero riding position has given rise to the stigma of aero bikes being uncomfortable and uncompromising – not an issue if you’re a conditioned athlete with a team of physios working on you but can be problematic for the everyday cyclist. It’s with good reason that aero bikes are reserved for the short-course time trials and that different bikes are needed for distance stages, mountain stages, and sprints. The real-world performance gains of these aero bikes are further challenged upon scrutinising the standard models of wind tunnel testing: high simulated riding speeds of 48-64Kph (30-40mph), fixed bike and rider positions, flat terrain, riding in clean air (no other riders in front or behind). The real-world likelihood of this being recreated are about as slim as the chances of you being a pro-tour rider. . So how important is an ‘aero’ frame? we know that a rider accounts for about 70% of wind resistance (range of 60-80% depending on rider position). Of the rest, wheels/tyres account for about 10%, and the remaining drag comes from fork, handlebars, cables and frame. Of course, all this goes out the window when we add the necessities of water bottles, lights, saddlebags, pumps, GPS and so-on. The reality is the frame only commands about 7% of total drag. An ‘Aero” frame is, at best, about 40% more streamlined than a non-aero type. Crunch the numbers and that means using an aero frame gives roughly a 3% advantage. And wind-tunnnel tests show this advantage only occurs at high speeds (>40km/h), in clean air, when riding on your own… That advantage is important if you are chasing a podium finish in a time-trial. For anything else these stiffer and uncompromising bikes become physically draining to ride on anything other than a smooth, flat road. And of course that aero frame has little benefit in a group ride. So that begs the question, are these aero frames worth it? In our experience, bikes should be aero-optimised, not compromised: The cockpit, wheels, fork, and headtube create the ‘leading edge’ of the bicycle (those parts that contact the air first). These have the biggest effect on drag, so prioritising these parts for aerodynamic design leaves the rest of the frame to look after the rider’s comfort and efficiency. With aero bars, aero wheels, aero fork, and refined riding position - we can make significant aerodynamic improvements without the need, or compromises, of an ‘aero’ frame.


Weight: How light can you go?

We’ve all been guilty of at least one of the following: Picking up your friends new bike as if our hands are digital scales. Buying a carbon bottle cage because its 6g lighter. Skimming through in-depth groupset reviews to find weight figures, or trying to convince ourselves (and others) that disc brakes aren’t worth it (lol) – the list goes on. Everyone enjoys riding lightweight bikes because of the way they feel – they’re responsive, agile, and lively. However, there are lightweight bikes, and then there are ultralight bikes. As the old saying goes “Everything is poison, it’s just the dose that kills you” As frame designers we’re constantly impeded by this annoying thing called ‘physics’. We desire to create indestructible featherweight frames that are stiff and flexible and corrosion resistant and aerodynamic and compliant and….. then ‘Old Man Physics’ calls the cops: every action has an equal and opposite reaction. To make frames lighter, you reduce tube wall thickness or diameter. The compromise of which is more flex and reduced durability. Intelligent engineering and material selection can help soften the compromise, but the compromise will always exist. Ultralight race bikes may give you marginal gains on steep climbs but to us the compromise is problematic. Symptoms include poor handling as headtube flex impedes wheels tracking, poor durability as paper thin tubes are susceptible to damage, and poor driveability as the frame fails to transfer large power loads. The real world performance value of such lightweight bikes is questionable, just play with this calculator and you’ll find that the weight wheenie argument doesn’t ring true for the nonprofessional rider. Let’s look at the example below:

6.8kg UCI Race Bike + 75kg rider
2km climb
7% gradient
Power 200 watts
Time = 10 minutes and 55 seconds

7.5kg Titanium Road Bike + 75kg rider
2km climb
7% gradient
Power 200
Time = 11 minutes

A grand difference of 5 seconds for a steep 2km climb. If the rider on the heavier bike exerted an extra 1.5 watts, he would match the pace of the rider on the ultralight bike. To pull this into perspective, 1.5 watts would still be within the margin of error in any high-end power meter, it’s negligible in the real world. For a pro-tour rider this may be the difference between a stage win and not being on the podium. Their bikes, however, don’t need to last more than a season so the compromise is tolerable. Unless you ascribe to the idea of living in a throwaway world, a true road bike needs to last in order to perform. They will be used and sometimes abused and, let’s be honest, s#*! happens. Your bike will be dropped, it will be mishandled in transit, it will be slammed into potholes – and that’s just part of life. The question is, how much of your passion (and hard-earned wage) is disposable?


Stiffness

In its simplest form, frame stiffness is generally tested in two areas - headtube flex and bottom bracket flex.  Headtube flex is linked to the trackability of the front and rear wheels and generally speaking good headtube stiffness (in moderation) results in good handling. Bottom bracket stiffness is linked with the driveability of a bike.

Historically bike builders believed the stiffest frames were the fastest frames.  Whilst this concept still prevails in modern bike design the reality is starkly different. Recent studies have proven that not only are compliant bikes significantly more comfortable and energy efficient, but they help deliver the power more effectively throughout the pedal stroke. In compliant frames, the bottom bracket moves inboard when loaded and has energy ‘stored’ like a spring, when the load is removed (i.e. past 6 o’clock in the pedal stroke) the bottom bracket begins to move back to its natural plane and that stored energy gets transferred back into the drivetrain. This gives a smoother, less jerky, pedal stroke. 

Overly stiff frames suffer from poor handling causing tyres to lose traction on uneven surfaces and steep decents. Stiff frames are also notorious for transmitting road noise and chatter, the exhausting and spirit-crushing bane of bike riders. It’s ironic that frame manufacturers promote how super-stiff their frames are yet use all sorts of component gimmickery to make them more compliant.

So are highly flexible bikes better? Unfortunately it’s not that simple. What you to do to one area of a bike frame affects every other area of the bike. If you drastically reduce stiffness to make a frame more comfortable, you will inevitably impact handling. Apart from this, durability will decline and the most highly stressed areas of the bikes will inevitably fail. We design to create a state of equilibrium. We need enough stiffness to refine ideal handling characteristics and driveability, we need enough flex so that our bikes are comfortable and characterful.

Our Design Philosophy: Bikes that are aerodynamically optimized but not compromised, that are lightweight, durable, compliant, and honestly priced.  So how do our designs reflect our philoshophy?

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