Originally Posted by
IcySmooth52
I don't mean to argue, but I work in the cycling industry an am an engineer. A higher modulus is greater stiffness, but carbon isn't like metal where such a measurement is equal in every direction with all other variables removed. (ie, a block of it)
Carbon however doesn't act like that, and the fibers that are higher modulus are only stiffer in one direction. In all others, they're more brittle. They don't use the same modulus fibers everywhere on a frame because they don't even want it stiff everywhere (seat stays). But where it's using higher modulus fibers, don't put it in a vice.
You're not arguing, because you are saying the same thing we are. Using stiffer fibers may give a stiffer bike, or it may not. It depends upon how much is used and how it is used. The goal of using stiffer CF may be more stiffness, or it may also be lighter weight or both. One thing for sure, the carbon make up of a CF bike is never just the highest strength and stiffness fibers that are alluded to in the specifications. Those strongest, stiffest fibers comprise only a fraction of the total weight of the carbon, placed judiciously for maximum positive effect with minimum drawbacks. So a Hi Mod bike is no where near all Hi Mod CF.