i don't want to appear abstruse or argumentative. i'm just going to tell you how i approach this. the chart you present is from a slowtwitch article from about 3 years ago and, as well as i remember (from memory) relies on drum testing. what we know - what i think i know - is that drum testing has a problem, but that this problem is generally overlooked because while drum testing is not reliable at telling you a tire's optimal pressure on a given (or any) course, the relative values are reliable. meaning, it can't tell you what pressure your conti 5000 should run at, but it's reliable at telling how that tire stacks up against a schwalbe pro one tt. is that fair? are we agreed on that?
this testing on the rolling road caused me to ask two questions of the data: first, on the 808, why don't pressure increases require greater or less power expended by the rider? second, are the optimal pressures for the 858 unreasonably low?
but sauce for the goose is sauce for the gander. if relative values are acceptable for drum testing, why aren't relative values acceptable for rider-on rolling road testing?
we lost my favorite theologian this week. frederick buechner died at the age of 96. i remember reading many decades ago from a book of his and he tackled the inconsistencies in the synoptic gospels. how can irreconcilable data presented as fact occur in the inerrant word of god? buechner's answer? "somebody [matthew, mark, and/or luke] made a mistake."
this closely aligns with slowman's 7th law of epistodynamics: shit happens. but shit happens against the landscape of what we have that is valid. you believe that with drum testing. so do i. you don't believe that with rolling road testing. why do you accept the known problem with drum testing but reject rolling road testing? don't they both offer value in the *relative* even as we know there are issues in the *absolute*? if we can't stipulate to the reliably good while acknowledging the imperfect, then rolling resistance data and christianity both have a big problem.
Dan Empfield
aka Slowman
this testing on the rolling road caused me to ask two questions of the data: first, on the 808, why don't pressure increases require greater or less power expended by the rider? second, are the optimal pressures for the 858 unreasonably low?
but sauce for the goose is sauce for the gander. if relative values are acceptable for drum testing, why aren't relative values acceptable for rider-on rolling road testing?
we lost my favorite theologian this week. frederick buechner died at the age of 96. i remember reading many decades ago from a book of his and he tackled the inconsistencies in the synoptic gospels. how can irreconcilable data presented as fact occur in the inerrant word of god? buechner's answer? "somebody [matthew, mark, and/or luke] made a mistake."
this closely aligns with slowman's 7th law of epistodynamics: shit happens. but shit happens against the landscape of what we have that is valid. you believe that with drum testing. so do i. you don't believe that with rolling road testing. why do you accept the known problem with drum testing but reject rolling road testing? don't they both offer value in the *relative* even as we know there are issues in the *absolute*? if we can't stipulate to the reliably good while acknowledging the imperfect, then rolling resistance data and christianity both have a big problem.
Dan Empfield
aka Slowman