Originally Posted by
burnthesheep
In a cross wind a modern "U" shaped or optimized profile 60mm wheel is about the same as something smaller than 50mm in the classic "flat sided vee".
Essentially, with the older deep wheels the cross wind was pushing against a flat side wall on deep section wheels. Nowadays that profile facing a cross wind is somewhat curved and profiled. So, it presents less resistance to the cross wind.
Think of it like the old deep wheels were the shape of a wedge with a tire on top. The new ones are the shape of an oval with the tire as part of the oval.
But, we're talking probably in the early 2010-teens or earlier for that cheap flat side profile vee.
For me, running Jet 4's (45mm) were fine until I got into the 140's. Granted, these are 2010 wheels so your conditions apply (def not oval). There are just too many windy descents in our area. Getting blasted with a crosswind that moves your front wheel while descending 45+ mph is one of the more scary things in this sport. I'm pretty sure the next bike I get will come with 50mm wheels, so we'll see how that goes. More than likely I am going to get some 30-35mm for road racing / training and use the 50's for crits.