Let's start by saying that on average, the difference between a carbon composite frame and one made of high-grade steel is around 500/600 grams, a weight that is certainly significant when related solely to the mass of the two frames, but becomes practically irrelevant in the overall rider-bicycle combination. For instance, considering a rider of 69 kg, the weight difference in favor of a carbon frame is about 1/150th of the total mass.
The FCI and UCI set the minimum weight for a professional road bike at 6.8 kg, a goal that is easily achievable today with a good steel frame.
Therefore, what can justify the rational choice of buying a carbon composite frame, mass-produced using molds, rather than a custom-made, fully customizable steel frame?
If we consider the various parameters of a frame for cycling use, such as stiffness, comfort, fatigue resistance, shock absorption, responsiveness, and so on, the choice of carbon fiber becomes highly questionable.
This is because in creating a good steel frame, a skilled artisan can easily adjust each parameter individually compared to a serially produced carbon frame, choosing, for example, steel type, tube diameter, sections, etc.
So how can the purchase of a 6.8 kg carbon bike be justified?
The only objective motivation, aimed exclusively at achieving the minimum weight, is that by purchasing a carbon frame bike, the goal is achieved while spending less compared to a steel bike.
Today, in fact, a good quality steel frame costs as much as a carbon one of equal quality, except that the latter, as mentioned earlier, weighs between 500 and 600 grams less.
This means that by opting for a carbon frame, it's possible to use cheaper and consequently heavier components. The result is that by spending less, it's possible to buy a carbon bike with the same final weight as a steel one with high-end components, but certainly not with the same performance.
Do you want to see a 6.4kg steel bicycle frame? Check out mine!
