Originally Posted by
Hiro11
I think you're confusing me with the OP. Personally, I already own both a carbon and a Ti bike. I like them both.Which is why I said "I can see benefits to both" in an earlier post and why I own both types of bikes. I'd like to see the physics behind this. Clearly the energy absorbed by the frame when flexing is returned when the frame rebounds. Is anything actually lost to the rider? I'm sure there's a point when yes, the frame is hurting efficiency, but the difference in deflection between an extremely stiff Foil and the noodiliest noodle ever made is probably not great enough to make any real world difference in everyday riding. The stiff frame may indeed "feel" different, but from any objective standpoint I've never seen proof that lack of relative stiffness in a frame will result in a provably inefficient frame. Again, the point of Lemond and co is not that they "chose" to ride noodles, it's that the times they posted in climbs on those noodles are still extremely competitive with times these days. I guess you could take a current day pro rider and send them up the Alpe on a Dogma and then on a 979 and compare, that might actually be pretty interesting.
I already said all of that.
"Top of the line" may mean a Spectrum custom Ti for some people. Also, most people aren't racing. Lastly, fashion clearly plays a role here.
In the end, I agree with your central point: ride what you like, independant of frame material.
Fashion has nothing to do with why virtually all top bicycle makes choose carbon for their flagship bikes.
Carbon bikes can be made stiffer and lighter than Ti bikes and why carbon is prized. Plus the differential stiffness of carbon as I explained earlier can be calibrated for a precise ride and maintain tremendous lateral stiffness.
As to stiffness and speed, this has been debated here before and many side with you and believe that frame flex aka potential energy is restored 100% with each pedal stroke and there is no difference in speed between a stiff and a flexible frame. My view is, stiffer is faster. This is just my opinion having owned many of each. I believe the physics derivation would be the same a spring in the context of the 1st law of thermodynamics. If a spring is excited and left to oscillate it will over time stop. It will not conserve energy...aka is not 100% efficient or it would violate the 1st law of thermodynamics and be a perpetual motion machine.
First law of thermodynamics: Heat and work are forms of energy transfer.
Energy is invariably conserved, however the
internal energy of a closed system may change as heat is transferred into or out of the system or work is done on or by the system. It is a convention to say that the work that is done by the system has a positive sign and connotes a transfer of energy from the system to its surroundings, while work done on the system has a negative sign. For example, changes in molecular energy (potential energy), are generally considered to remain within the system. Similarly, the rotational and vibrational energies of polyatomic molecules remain within the system.
From the above, all the energy associated with a system must be accounted for as heat, work, chemical energy etc., thus
perpetual motion machines of the
first kind, which would do work without using the energy resources of a system, are impossible.
Lasty, a stiff bike is prized by a pro and good amateur also because of added control throughout the pedal stroke which also relates to bike handling over rough road surfaces.
FWIW most feel the same about wheels...stiffer is faster even though many concede stiffer is less comfortable.