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If you were riding a loop on your road bike, which is relatively exposed with a decent bit of wind, would it be faster overall to climb into the wind, and descend with the wind, or have the wind assist up the hill and descend with it against you?
I had an awfully long time thinking climbing into the wind was probably not the right choice earlier today.
As it was, it was a moot point as the magical eternal headwind of the new forest was in force and I actually had a head wind on all sections of the bloody loop....
I think I'd rather have the assistance up hill, and ride into wind going down. I've no idea which would be faster though. I guess there must a point at which wind speed becomes a factor rather than just annoying though, but that probably varies depending on rider
I hate headwinds when going downhill... it was bad enough climbing up one side, I don't like having to climb down the other side as well!
Depends how strong the wind and how steep the descent is. If it's a long gradual descent and the headwind is strong enough that you have to pedal downhill into it, then I'd be climbing into the wind. Pedalling downhill into a headwind I find incredibly depressing, at least with a climb you know you're going to be having to put a load of effort.
I always try to climb into the wind, I figured that resistance increases as a square of your relative velocity, and since the relative velocity is the sum of windspeed against you + your speed into the wind, you might as well lower the speed into the wind as much as you can, i.e. by climbing 😎
Or you could just argue you'll be moving slowly and against a resistance anyway, might as well combine the two.
Anecdotally I noticed the headwinds less if I climb into them than if I'm working on the flat.
I’d suspect I’d want the wind assistance on the part of the ride where I was spending the most time working hard. For me that’s the uphill part of the ride. Speeds are higher downhill, so the headwind has more effect at any time, but the total downhill time is also much shorter, making the overall benefit there less consequential.
Hills i can do, wind i can do. Hills and Wind together. Ooft.
I'll take the headwind on the downhill
https://www.cptips.com/windrde.htm
snip.... each 5 mph of wind speed equals ~1% of grade i.e. a 20-mph headwind would equal a 4% hill
snip…. each 5 mph of wind speed equals ~1% of grade i.e. a 20-mph headwind would equal a 4% hill
I'd never thought of it in those terms but that seems about right.
Had exactly this scenario this morning.... 33km ride into a valley, constant uphill gradient that wasn't really noticeable other than I felt weak. About 250m of elevation gain.
Had a coffee and a focaccia and headed back down the valley. Needed my wind jacket and a Buff due to the north wind. Wasn't as slow as on the way there, but wasn't exactly freewheeling, either.
Id probably rather climb into the wind. But then I like climbing and always struggle with pace on long flatter road sections so hate headwinds there.
The force wind exerts on you is proportional to the square of the wind speed - I think.
So when climbing the force the headwind exerts on you is lower as the head wind + your speed into it is less.
When you're descending you're going much faster, so a tail wind will help lower the resistance enabling you to go much faster. This only becomes a problem if you max out the speed you're happy travelling at downhill
Climbing into a headwind should I think be the most efficient.
Any energy you put into the climb you reclaim on the descent*
Any energy you put into air resistance is lost, and it's a cube law so you want to minimize it's variability**. So the aim is to average out the airspeed as far as possible.
Same reason a TT isn't an FTP effort, you still push hard on the climbs and recover on the descents.
*In the real world you don't because of the air resistance being proportionally higher on the descent.
**Riding a fixed distance, at 2x normal speed takes 4x the power, so uses twice the energy even in half the time.
For a constant power throughout the loop, I think I'd agree with 13thfloormonk. Take your headwind when you are going slow anyway.
Although also consider the secondary effects:
Descending with a tailwind could lead to wasted effort or inability to use your power if you are needing to brake anyway. [tertiary effect, this could give you a "free" recovery period benefiting you on the next climb]
Riding at exactly windspeed means you have no wind cooling and you get hot quickly (assuming you were correctly dressed for the conditions otherwise).
It's always a headwind ! Sods law.
Just reminded me of https://mywindsock.com/ , which I've not used for over 18 months.
Don't know if this will work, but as an example climb DT78 must surely have climbed, here's Wheely Down https://mywindsock.com/segment/626542/#
Don't forget about your position on the bike. It's a lot easier to get aero going downhill. I suppose it depends on the gradient on the climb as to whether you're dancing on the pedals with a full frontal resistance or grinding up a 5% drag whilst biting on the stem.
I once had to pedal all the way down into Llanberis due to a pesky northerly, which was mildly annoying.
For me it's about which is more fun (it's true, road riding can be fun). Getting a tailwind up a climb and feeling like a superhero is GREAT and I'd happily take a more pedally downhill to pay for it. The only caveat is that if the wind is such that it makes the descent feel sketchy then I'm not so keen.
I only ever really notice the wind on the flat. and if it's a loop it probably going to equalize out what ever you do, you're probably over thinking it.
Someone's already said it but I always seem to be going into a headwind, there and back
the magical eternal headwind of the new forest was in force
Yay, not just me then! Thought the verderers had invoked witchcraft on me for straying off the designated routes.
Oh, wait - New Forest and hills, must be somewhere else 😉
Pedalling down a descent into a headwind is horrible. On a descent you know is good for 40mph and you're there churning away struggling to get above 25mph.
I'd rather climb into the wind, at least you're going slower anyway.
The worst thing is swirling wind or on a descent with lots of hairpins so you're constantly getting headwind > crosswind > tailwind > crosswind as you turn.
Someone’s already said it but I always seem to be going into a headwind, there and back
You probably are, it's relatively rare for wind speeds to be consistently higher than typical road riding speeds.
Fixed gear riding into a headwind. In a too big gear. There is nothing more demotivating than seeing your cadence drop to sub 50 on the flat.
What zomg said - you'll save more time on the climb than the descent.
Depends on the hill, but you often get a shielding effecting from the headwind when climbing the hill, so I’d go up into the wind.