Originally Posted by
CargoDane
60 kph is 37 mph. For comparison, When I hit 45 kph (downhill) I can really feel the wind. At 55 kph I spin out with my gearing (I am trying to become better at spinning).
In actual wind, I do try push through between the gusts.
On flat ground, I can hit around 40-45 kph before wishing for a heavier gear (not that good at high rpm spinning yet - I'm a natural masher), but truth be told, I'm not sure I could push the bike much faster on flat ground in a much heavier gear (at least this particular bike).
If you double your speed, you quadruple the wind resistance (force).
So, going 9 mph to 18 mph results in four times the resistance, and going from 18 mph to 36mph is four times that - which means that 36mph has 16 times the wind resistance as 9 mph. Yes, I did choose 9 mph because it came close to 37mph when multiplied by four, lol.
This is the reason for those time trial setups and why no one but Cubewheels stand up in strong headwinds.
60 kph/37mph is a Beaufort 7 - a "near gale". Something you most likely have experienced quite a few times, as most of us on here have (because it's not a rare wind strength).
Edited to add:
If going 20 kph (12.5 mph) into a 60kph/37mph headwind, the effective wind is 50 mph. That's almost highway speeds. There's an immense wind resistance at those wind speeds.
Like I said above, I am not defending his wind physics because I don't believe they're correct, just explaining how I deal with high headwinds in a manner that mitigates the aero effects. I'm not disagreeing with your math, I'm saying that people who are riding in such winds aren't really making progress except between gusts or when they can aim the bike out of the direct blast. Remember that a strong headwind can also be one hell of a great tailwind, and there's a lot of on-between impacts depending on where it's hitting you.
You and I aren't really disagreeing at all.