Originally Posted by
HTupolev
It's unclear to me how Bierman evaluates that equal drop against a flat surface is "equal comfort." At least under static testing, the spring rate of a tire
depends on the curvature of the object being pressed against it, with the deflection on sharper shapes being less dependent on tire width. This seems like something that really needs to get answered with vibration sensors, or at the very least by proxy by characterizing how tire width affects breakpoint.
I can't defend their testing protocol. What would you say about the same pressure in a 25 mm tire vs 32 mm tire, on normal roads (not Pave)? If you follow the 15% drop rule, you get about the correct pressure to maximize comfort. When the breakpoint is exceeded, where does this additional lost energy go? Seems to me much of it goes into your tissue wit some into the tire casing. The proxy for me is comfort. I run the narrowest tire that I can run, the one that is comfortable. Pressure can be a speed tradeoff. The optimal width for me is 28 mm but that is too tight for my bike, so, I run 25 mm.
The only "studies" that I recall that looked at vibration and where it was absorbed were at two Universities. The results were not compelling, but anyone who does long distance endurance events would believe them.