Originally Posted by
asmac
Thanks for pointing me to the link. Good stuff. It seems to confirm that construction and compound (i.e. suppleness) are more determinant of rolling resistance than pressure. I don't know how lower rolling resistance can not determine speed, all things being equal, or how the length of the ride factors into this. ???
Because all other things
won't be equal. They can't be.
As I mentioned above, rolling resistance
alone doesn't determine speed. The article explains it better than I can, but I'll explain it how I understand it. I hope my words make sense.
Inflate your tires so high that there is no deflection (deformation) at the contact patch. Viola, almost no rolling resistance. However, you've now eliminated the suspension characteristics of the tire and introduced harsh vibration to the ride quality. You legs and arms automatically behave as suspension devices to absorb/overcome the discomfort. The energy being consumed by behaving as suspension devices is robbed directly from the energy needed to propel the bike forward. Due to these losses, you are slower, not faster. The longer the ride, the more fatigue, the greater the losses.
Some of the experts agree that the amount of energy required to overcome a harsh, jarring ride quality is greater than the amount of energy required to overcome some rolling resistance caused by the contact patch deflection.
I tend to agree. And have since the early 1990s, when I abandoned low volume high pressure tires.