[amagumori]

ok, so i'm curious how people feel about this, but i believe, for road riding, wider tires actually do make you faster, to a point of diminishing returns around 32c, because of cadence.

when you hit a bump with high PSI / road tires, your wheel bounces, you're momentarily unweighted from the pedals, and that means your cadence is interrupted. anyone who has raced cyclocross knows; there's a LOT of skill involved in applying pedal strokes at just the right times to absorb bumps while also continuing to apply power, and it's way less efficient than just riding clipless on a freshly paved road. every bump "resets" your muscle contraction cycle, and after a bump, you're often not at the right crank position to apply a hard, sharp pedal stroke to try to catch up.

i believe a ton of efficiency is lost through this biomechanical effect on cadence alone, and that's saying nothing of how much energy you lose in the transfer of forward momentum to an upward bounce impulse.