When automobile engineers develop a new car, they nowadays already know before the first serial production what will happen to the passenger cell if the car crashes against a fixed obstacle at 50 kilometers per hour. An exakt knowledge of the material properties allow for computer simulations to be created which mirror reality almost par for par. With bikes, this is unimaginable.
The diamond frame costruction has been existing for more than 100 years indeed. But up to now, we have come to know only vaguely which forces impact on the individual components of the bike. This didn't matter when bikes still were so heavy and robust that they often outlived their owners. Today, the road bike - just like any other object of utility - is subject to trends and tendencies much more than it used to be - and an important trend is low weight. Only very few manufacturers, however, calculate before serial production, how much material is needed where in order to build a light, but nevertheless safe bike; most of them just try until the compromise between weight and qualities like stiffness and stability roughly fits. But just roughly: There are definitely far too many bikes on the road whose low frame stiffness at least irritates their riders or - worse - brings them into trouble. And there are far too many documented cases of breaking stems, handlebars and seat posts.
Author: Dirk Zedler