it started with “Having tires narrower than your rims means potentially riding on carbon if you get a flat.” not rim strikes per se. I’ve had tires wider than rims and had rim road rash on both aluminum and carbon. With carbon you want a good warranty. In either case (wide or narrow tire/rim), for road, the Air-Liner will give some protection in this situation. And the more dangerous sudden loss of pressure while traveling at high speeds. Without impacting rolling resistance.
To bring it back to the Specialized CLX 50 wind tunnel video, the results over 40km / 25 miles:
No wind, time saved on CLX50 vs SLX24:
- 20-sec saved on 26c tires, over 40km / 25 miles
- 16-sec saved on 32c wide tire, over 40km / 25 miles
- 12-sec saved on 42c gravel tires, over 40km / 25 miles
Crosswind:
- 60-sec saved on 26c tires, over 40km / 25 miles
- 48-sec saved on 32c tires, over 40km / 25 miles
- 40-sec saved on 42c gravel tires, over 40km / 25 miles
So that was a mid aero wheel vs a shallow box wheel. Some level of marginal gains but hey I benchmark myself against myself on some local 1 hour segments. So I got aero wheels with great handling in crosswinds because its usually very windy and gusty when I ride.
On to tires and @NoodleNelson question. Practically speaking, even on a 25mph fast weeknight group ride I would not expect much aero difference between 25c and 28c GP5000 S TR tires, or 26c and 28c/32c Vittoria N.EXT tires.
Example. Our Wed ~25mph loop is about 22km / 14 miles, and plenty of crosswind, so the aero difference between running 26c vs 32c might amount to, best case, 6-8 seconds over 34 minutes? Hard to take those wind tunnel results and apply them to a group.
Given that, where I focus is on reducing downtime from a flat. Because with a flat nearly everyone goes bye bye and you are standing on the side of the road. Which is the point of tubeless, because around here, nearly every Wed group ride has somebody getting a flat. And if you’ve ever had close calls on tubes/tubeless at high speeds, like I have, the Air-Liner is an extra measure of safety.