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As I said, the Rovals that Sagan was on are designed for the 30mm tubs he used.
The "more aero" for wider rims/tyres works because people are using wider tyres not because they are just more aero.
If you could run 20mm wheels/tyres without other issues they'd be more aero than 30mm.
Going to 50mm still means you have more frontal area and are less aerodynamic and in fact going so wide will need fork and frame redesign which will worsen aerodynamics even more.As the same pressure, a bigger tyre's Crr is better than a skinnier tyre's. But you don't run bigger tyres at the same pressure, you run them lower, which increases Crr. Even if you did run them at the adjusted-for-comfort pressure, as you say, the Crr is basically the same, so no advantage in going wider, just disadvantage due to worse aerodynamics.
Being able to ride at 20kph to your bloke with the spare wheel or until your car reaches you saves how much time vs. standing on the side of the road? Are you really using VDP's crash as a rideability example? He pinch flats failing a bunnyhop at 50kph+ and then rides one-handed onto the footpath but crashes because he hits a hole he didn't see because he was looking at his flat front tyre?
hippy-
oh are they? you said they were 29mm rims. if that is the case then my point isi more invalid.
obviously wheel aerodynamics are much more complicated than frontal area. obviously nobody runs 20mm tires anymore...
and no that isn't right about crr. the link i put in my last post shows this with the gp5000. if you inflate to the same tire drop, or casing tension, and the tires are made of the same compound, the crr is the same.
yea maybe mvdp wouldn't have pinch flatted in the first place, or maybe he'd of retained a more rideable pressure.
i watched the footage a few times and couldn't see really what took him down, and different news outlets have all said different things. his wheel was not in line with his bars when he hit the ground though, so idk what is going on.
zmjones_
the aerodynamics rule is rim must be > 1.05 of carcass width. as far as i know the only aero rim for 30mm tubs is the enve 4.5 ar disc. so i don't think there is much difference.
the crr for a wider tire with the same compound is basically the same for the same casing tension. https://www.bicyclerollingresistance.com/specials/grand-prix-5000-comparison
in any case not bottoming out would massively reduce your probability of flatting. not like they are putting sealant in tubs either.
skeptical of the idea that the "rideability" of a flat tub is really that important. you can't ride very well. e.g., mvdp's flat at de ronde. but maybe i'm wrong.