A bicycle, it goes without saying, is the best Christmas present ever, but with the possible exception of a puppy it’s also the most difficult to wrap. So pity the poor frame designer who has to wrap and drape carbon around its complex curves such that, when baked and finished, the frame delivers the desired ride feel. The construction of a carbon fibre frame is a complex 3D puzzle that eclipses the Rubik’s Cube. The beauty of carbon is that, unlike metal, multiple pieces can be layered at varying degrees of intersection and overlap to give very tight control over the performance attributes and strength required at any given point of a bike frame. The downside is that carbon is anisotropic – it’s stronger in one direction than another in a similar way to wood – which means strength is dependent on the direction of the fibres. For carbon to carry significant loads the forces must be directed along its fibres, which makes fibre direction absolutely crucial. A bicycle frame’s constituent sections experience forces in several directions, meaning the carbon fibres must run in several directions too. It’s why different layers have their fibres at different angles, commonly 0° (in line...