Jive Turkey

Is it better to sit more upright with a decent tailwind to take advantage of the wind like a sail or best to still stay in an aero position?

noisebeam

I don't know, but everyone guesses so...

Probably depends if you are going faster or slower than the tailwind. A 25mph tailwind you are probably going over 30mph, so aero helps. A 50mph tailwind you are probably going less than 50 so sail up.

Jive Turkey

That's what I was wondering.

If the tailwind is less than your speed I figured you should stay aero but if greater than your speed sit up but I'm just an amateur and wasn't sure.

bdcheung

ride like normal.

Jive Turkey

But I normally ride standing on top of the seat like a clown.

umd

As long as your airspeed is positive, it makes the most sense to minimize your frontal area.

DXchulo

I wonder how fast you really could go with a 50mph tailwind. The most wind I've ridden in was somewhere between 25-30mph, and I was easily cruising along at 30mph. I almost crashed in the crosswind a couple times, but it was worth it.

umd

If you had a true 50mph tailwind, that was exactly behind you and not gusty, you should be able to ride at least 50. Air resitance is the greatest force we have to work against (on level ground). If you were riding 50mph in a 50mph tailwind, you would essentially be riding in a vacuum, and the only force you would have to overcome would be rolling reistance.

Of course you would need a big-ass gear and spin like mad too.

If you think about it another way, the speed record is over 150mph, drafting a special vehicle that sheltered the rider completely from the wind.

noisebeam

Which is one reason why I said 'probably going less than 50'.

Brian Ratliff

There are very few times when your relative airspeed is negative and it would be advantageous to sit up. Most of the time, a tailwind simply lowers your relative airspeed, or rather, you raise your ground speed to match what your normally encountered airspeed.

The only times I've traveled at the same speed as the tailwind have been on climbs. That's because gravity is the main force I am fighting, as opposed to air resistance. Otherwise, if I'm putting out enough power to go 20mph in still air, with a 5mph wind at my back I'd be cruising at 25mph and still have 20mph wind in my face.

botto 

yes.

umd

It's only like 130rpm in a 53x11

merlinextraligh

And the times that your air speed would be negative are pretty darn rare. If you have a tailwind, exactly blowing in your direction, and the windspeed is faster than your riding speed, you would have negative airspeed.

But if the wind is a few degrees off from a perfect tailwind, then it's going to still make sense to get aero, even with windspeed above your riding speed.

This calculator demonstrates that.

https://www.hedcycling.com/aerodynami...calculator.asp

noisebeam

Another nutty drafting record is by Michael Secrest - drafting truck to cover over 1200mi in 24hr for ~51mph average.

Phantoj

That can be rough on a hot, humid day...

jsharr

I find it easier to ease the main sheet and watch the tell tales if I sit up when sailing, I mean riding with a tail wind.

Brian Ratliff

Tell me about it. Last time I experienced this was on a hot day at about 4:00 in the afternoon in a race in eastern OR (why the organizers thought starting a race at 2:00 in the afternoon on a 90+ degree day was a good idea, I'll never know). I was off the back after getting dropped for the second time, pushing 250-300W up the hill. Felt like I was working the trainer in an oven. I actually started getting chills ... which I think means the start of heat exhaustion. Not good.

RacerOne

If you don't feel like there is a headwind, you're not going fast enough.

carpediemracing 

I don't have my post up (it's been in draft for a year or something). I rode in the Key Biscayne area just as Hurricane George hit. When we went out it was steady 50 mph winds, gusts to 80 mph. Since we went down there to do the Coconut Grove race, I had just TriSpoke/HED3 tubulars. I coaxed my teammate and his then gf to go out and ride with me. We struggled in our bottom gears going south but coming back... sitting up and coasting we'd go almost 20 mph. 54x14 up the Key Biscayne causeway bridge thing, going easy.

I told my friend I had to do a sprint with the tailwind. So I took off as hard as I could, spun my 54x11 as fast as I could. Did 60 mph for about a minute, limited by my ability to spin really fast for a long time. Passed a car on the road next to me.

Tons of fun.

cdr

tubescreamerx

how did the HED3 handle in those windy conditions?

coasting 

i only notice headwinds. maybe i've ridden in tailwinds but i would rather assume it was my enormous legs making me go faster

carpediemracing 

They were sketchy to say the least. We were all friends, rode together a lot. They used to do Thursday Night Sprints with me, he was my leadout man when we raced. We really knew each other well. So we and we rode in pretty tight formation going south. I remember a few times going sideways pretty hard. Since even a slight angle meant a vicious echelon (due to the high wind speeds) I'd usually be staggered in the safe direction off the next wheel. At times we were riding pretty much right next to each other.

I also had a pretty hard grip on the bars, much more so than normal. "Death grip" comes to mind.

When I was sprinting I remember wondering if the front wheel would take off sideways. I tried to keep my weight on the front of the bike. I basically jumped out of the saddle for only a couple downstrokes then sat down and spun.

I guess I'd do it again, with bigger gears, if I had a chance.

cdr

FLvector

Hey CDR,
I think I've heard that story somewhere before.

carpediemracing 

Ha! Hey! I hope the Suncoast is treating you well.

I saw my first mosquito of the season a couple days ago. I think the cold for the next few days will take care of them though.

FLvector

Yes. And the armadillos are plentiful this year.