following on my post just above, here’s the 404 firecrest released maybe 2 years ago? i think?
this is kind of an outlier on wheels like this, with fat inner bead widths and especially (but not exclusively) hookless. this should’ve given me a clue about the 808 firecrest just launched.
here’s the 808 firecrest. i suspect - but don’t know for sure, because i don’t have it - the 858 NSW is fatter. but i don’t know. cyclingtips was right, at least about the 808.
Check me if I’m wrong…but doesn’t the “rule of 105%” apply to the WIDEST section of the rim, which is not necessarily right at the rim edge (i.e. what we used to call the “brake track”)? Just thought I’d point that out for future measurements you take.
Also, don’t forget that this ROT is referring to the point at which aero degrades “too far”, and not so much the “optimum” ratio for aerodynamics. THAT is why an 25mm tire on these new wheels may be still significantly faster than if they have 28mm tires on them. It’s OK for Zipp to test the new wheels with the 25mm tire “for consistency of comparison sake” to older data, but they really need to show what happens when it has the 28mm tire on there, since that’s how it’s going to be used (per their recommendations). You KNOW they have that data (if they didn’t take that data, that brings up some big questions), so not showing it implies there’s something there they don’t want the consumers to see.