I think than Valverde used a 28 mm in a Roubaix and at the end of the race said that it was too much and not worth of the extra weight and front section.
Every pro is riding on 30 or 32 mm now. Of course the rims are totally different and wrap those tires in a way that the old metallic rims could not do, hence the aerodynamic gains.
Edit: I've got a gravel bike with 42 mm tires and a 28 mm set. I use the 28 mm when going in the hills on asphalt. I'm with you on that: it's a day/night difference. On mixed mostly flat terrains the 42 mm tires are the best compromise.
In the days of rim brakes a wheel had a finite life (the length of time it took to wear down the braking surface). Then shimano and the frame builders pushed everyone to disc brakes, so the wheels now last for ever. What do you know, 2 years later all the wheel manufacturers are claiming “wide is better” and flogging everyone new wheels.
I’ve not seen any clear evidence that they’re right, and there’s lots of intuitive reasons to think that wider tyres will be slower (aerodynamics!). I remain sceptical, but genuinely hopeful that someone who thinks that wider is faster can provide me with some solid evidence…
I am 100% sure that in this age of "marginal gains", the pro tour teams would not go for anything that doesn't give them it unless severely hamstrung by sponsorship deals. And I doubt that the wheel sponsors don't have multiple sizes available.
And I think you're severely overestimating wheel life span for modern models, at least due to the fact that carbon is more brittle than more pedestrian materials. Just look for Pogacar's fall earlier last week in the Giro to see how a simple flat tire makes the whole wheel a risk.
My experience is personal, but I get 50,000km out of a set of rim brake carbon wheels ridden in all terrains and conditions and through northern european winters. At that point you're also starting to lose spokes/nipples to corrosion, but the rim could be rebuilt with new spokes and a new hub if it didn't need a brake track. That riding includes racing, crashing, potholes, punctures.
Pogacar rides on Enve wheels, which are now hookless and therefore a puncture is much more likely to result in damage. Another innovation that makes life worse for the consumer and better for the manufacturer.
If you look at TT equipment all team members use the same helmet regardless of the fact that helmet performance varies massively from rider to rider.
The 2016 S-works Venge is 5w faster than both the SL7 and SL8, so on flat stages all specialized sponsored teams are riding it... aren't they?
Why is nobody wearing a TT Helmet and visor on a normal road stage?
The aero drag of wider tire is not a lot. It is more the wider tires are not slower. Wider tires allow: more air volume in tire, lower PSI. In turn those help ride quality.
A narrow tyre on a wide rim is a wide tyre. They don’t explain or address this issue. I suspect they would have used a wide rim with all the tyres, which is notionally a sensible thing to do, but in reality it’s completely flawed.
What are the results if you used a narrower rim with the narrower tyre so that the frontal area was actually reduced as much as it could have been?
I think the push to wider tires and lower pressures on road setups is actually because hookless carbon rims are much easier to manufacture than clinchers, and hookless tires can't handle 80+ psi.
Clincher carbon wheels are basically considered a niche product by big manufacturers
It's always: this is the latest model, it has these features, thanks.
I've got a road bike and a gravel bike. A while ago, I did the same workout, 12 reps of a local hill, 2.5 hours or so, once on each bike, separated by a week.
The road bike is 8kg and 25mm tires, the gravel is 12kg and 650bx42 or 48 tires. (might have been either, as I switched tires around then). The difference in time was 6 seconds.
The gravel bike doesn't feel as fast. It doesn't reward spinning, and the gearing jumps are just a little big for me (1x11). The road bike beats me up with vibrations, but it feels better climbing and standing. It's got closer gear ratios, so it's just a bit better matching. Now, to be fair, the gravel bike is running far better tires, so there's less resistance there. (and, that's basically why I bought it) But overall, they are basically the same speed, even on a hilly climbing workout.
So, the weight difference of 28 vs 42 is going to be 100g maybe. It's not a lot. Weight vs aero experiments have found conclusions like weight over 100 miles is tiny small compared to any aero gains (talking like +3 lbs having a few minute difference over hours). Which is to say, the effects you describe are pretty small when measured.
Moreover, the choice of 28 vs 42 is rare, feels like is more choosing 25, 28 or 32; or choosing something in low 30s compared to 40s. Meaning, the weight delta is even less in real world choices. What's more, you can go to 650b and have the exact same tire weights with much bigger widths.
Remember that the wider tires are more efficient at lower pressures than narrower tires. However as the pressures go up, the difference becomes smaller. Even without aero gains, the narrower tire will be faster provided its a smooth surface.
