Question

Suggest a reason, other than cost, that explains why fewer frames are made from carbon fibre than aluminium and titanium

Answer 1

The primary advantage of the material is that at a given stiffness, carbon fiber is significantly lighter than aluminum, steel, or titanium.

This lower density also means carbon frames do a better job of absorbing (rather than transmitting) road vibration, which translates into a more comfortable ride. And carbon fiber can be formed into complex shapes, giving bike makers greater creative design latitude. This is especially useful when trying to maximize the aerodynamic efficiency of a frame.