+2
14-04-2025 22:50
+0
13-04-2025 14:16
13-04-2025 05:18
+1
07-04-2025 22:02
07-04-2025 01:27
06-04-2025 14:25
06-04-2025 14:21
04-04-2025 22:27
04-04-2025 22:25
04-04-2025 22:20
+2
acem82
It looks like either year, they were sponsored by Specialized. Good to know.14-04-2025 22:50
+0
acem82
(I was really replying to the other person...) In Paris Roubaix, the bits with the cobbles are slower than the paved sections, so wind resistance is less than it otherwise would be on a "flat" road, though as I keep pointing out, these are equivalent to a bunch of little hills. While momentum will help one maintain velocity given resistances, you aren't taking into account that one had to get that extra mass up to speed in the first place, which costs more power. So, you do get back most of the extra power you've put in, but that's not helpful. The less rolling resistance (and climbing over the bumps) of less mass will always be more helpful than having more mass, all else held equal. Actually, this could be easily demonstrated with a cyclist on cobbles, 2 runs, start at the same velocity, do the same power, have a backpack full of foam on run 1, then full of rocks on run 2 (ensuring the PSI was perfected for both) and see which run went faster. And when we think about it, we know which one will be faster intuitively.13-04-2025 14:16
+0
acem82
Rolling resistance goes up with weight. Also, I did specify "all else held equal".13-04-2025 05:18
+1
acem82
The other issue is that Mad Petersen and Wout would have let MVDP do most of the work, as he kept showing he was stronger. MVDP did the strategy with the highest likelihood of victory, he just wasn't strong enough.07-04-2025 22:02
+0
acem82
You have to keep all else held equal or you're not isolating the change. A lighter rider is faster at everything, save downhills, all else held equal, as I keep showing. As for wind, just as in flat TTs weight basically doesn't matter, except that lighter equals slightly less rolling resistance. In the same manner, for a 30 kph headwind, weight doesn't matter, as the relevant equation is power vs CdA. The reason why more weight is helpful downhill is the same reason it's hurtful uphill, it "gives back" the energy (not speed) you gained by going up the hill. Lastly, in a sprint, weight is again counterproductive, assuming one has to accelerate up to speed. Accelerating a mass takes energy, and a heavier one takes more energy than a lighter one. Now, at most sprint speeds, almost all energy goes into wind resistance, but the acceleration of mass still does play a part.07-04-2025 01:27
+0
acem82
If you throw 2 identical golf balls at the same speed, but one is twice the weight, it will go a bit farther (wind resistance is the same, so the amount of energy of the heavier ball is higher). If you throw 2 identical golf balls at the same power, but one is twice the weight, it will go less far (the amount of energy is the same, so the lighter one is going faster). Remember that in a flat TT, once up to speed, the amount of weight is basically negligible (except a tiny amount of increase in rolling resistance). It's all power vs CdA. Probably the best way to think about this is with a truck (with a covered bed) over a flat but very bumpy road, and ideal tire pressure for the weight. Now, load the truck up to 3X the mass, change the tire pressure to the new ideal pressure, and do the run again. What will take the most amount of power? It's quite obvious that it's the run with the more mass. (Many of us have done this test in real world conditions without realizing it.) Why? Because there's deformation loss to the tire, which is somewhat worse when there's more mass, but there's also the loss from having to lift that much more weight over and over again.06-04-2025 14:25
+0
acem82
...Cause cycling at this level is always about the compromise of weight vs power. Pogacar could be stronger at a higher power, but his power to weight ratio would suffer. All else held equal is very important to understand they physics here, but that's *never* how cycling actually works.06-04-2025 14:21
+1
acem82
You might bounce more for the same power, but not the same speed. Sending 20 kgs over a jump at 20 kph will fly just as far as 10 kgs at the same speed. Again, Galileo demonstrated this.04-04-2025 22:27
+1
acem82
So, you're saying that doing a bunch of small hops on a bike is easier if you're heavier? Why do people buy lighter bikes, then? Why do they generally feel better and faster? An appeal to "rhythm" is not helpful either, as the right "rhythm" might be on the lighter or heavier side of things, and as it varies, it's likely a wash either way. Then we are left with the physics truth that it takes less power to lift lighter things than heavier things.04-04-2025 22:25
+2
acem82
No, weight doesn't affect the ability to go into the wind at all. It's all CdA vs power at that point. For example, it's "obvious" that a heavier object falls faster than a lighter one. But, absent wind resistance, it's not true (Galileo demonstrated this). An appeal to "obviousness" doesn't matter when the physics is clear. And yes, you have to be able to hold everything else constant, or you can't determine anything! So, imagine a 300 watt rider at 80 kgs with a CdA of 2.0, then imagine that same rider at 70 kgs with a CdA of 2.0. (Assume ideal tire pressure for both, same bike.) Which one can ride over a bumpy road fastest? The lighter one, as he doesn't have to lift as much. That's also why when they test bikes on 5 star cobbled sectors, the MTB goes faster than even a cobble-build road bike. Even though rolling resistance is higher on a flat road, and the CdA is junk, it smooths out the cobbles, allowing the person to not lift as much as they otherwise would.04-04-2025 22:20