What difference does the wind make?

Headdy

I do a regular 50km spin that usually takes 2hrs/2.05. Today after changing the saddle height (which I had thought made a difference over 5 miles last Sunday) I completed it in 1.47 a 30% improvement! the wind was at my back a lot during the cycle (not always the case previously). My question is before I get completely disheartened next time out can the wind be the 30% difference?

abbeyside1

Ina word YES!Sorry!;)

fletch

Yes it can....there was a 50kph West wind today in case you didn't notice! What direction were you heading?...I'm guessing East?

Headdy

Yeah east - didn't realise it was that windy, I suppose you never do til its on the nose!

fletch wrote: »

Yes it can....there was a 50kph West wind today in case you didn't notice! What direction were you heading?...I'm guessing East?

feck sake lads

great training though riding hard into the wind;)

TheBlaaMan

It might do...............



on the other hand........




your maths might be screwy

I make it 10.8%, at best.

Keep_Her_Lit

The wind makes a BIG difference.

An easy way to appreciate this is to do an out-and-back time trial* on a reasonably flat road (so that you can discount the effect of gravity). Pick a day like today, when you have a good headwind in one direction and a tailwind in the other. Record your times on the way out and the way back, then compare them.

The comparison will just confirm what you experience during the ride - that you feel like a gifted champion with the wind on your back and a geriatric tortoise when it's in your face.

But take it as a challenge, as advised by "feck sake lads", and get stuck in!

(* you start and finish at the same place; you go out the road X km, do a U-turn, then ride the X-km back to the finish)

Beasty

The bike calculator can give an idea of the impact of the wind

Assuming 200w power output, and using the 70kg rider example, with a 10kph headwind, average speed is just under 26kph, with an equivalent tailwind just over 38kph - implying you can go 50% faster with the tailwind than with the headwind

Of course, this is illustrative, but my own data is broadly in line with what the bike calculator indicates.

I would add that actual wind speeds clearly fluctuate significantly, both in terms of speed and direction. You also get more shelter at ground level, but you can see from this the scale of impact of different wind speeds on bike performance

mgmt

Heres a great website for checking out the wind.

http://www.xcweather.co.uk/GB/forecast

dquirke1

Keep_Her_Lit wrote: »

An easy way to appreciate this is to do an out-and-back time trial* on a reasonably flat road (so that you can discount the effect of gravity). Pick a day like today, when you have a good headwind in one direction and a tailwind in the other. Record your times on the way out and the way back, then compare them.

I tried this about two weeks back when we had a fairly strong wind. Rode west for an hour, turned around and took 1:42 to get home.:mad:
I was not amused.

Lumen

TheBlaaMan wrote: »

It might do...............

on the other hand........

your maths might be screwy

I make it 10.8%, at best.

24kph before.
28kph after.

That's a 17% improvement in terms of speed.

Headdy

Wow.thanks for all the feedback my maths were mad apologies and now not sure whats right but its irrelevant cos either way I'll be miserable next time out!

Rallymad

Give me rain any day hate wind was out wednesday on a 50k spin wind in face for first 20k then cashel to two mile borris wind accross me but not a problem was flying really put the hammer down trying to keep bike up to 40kph peddling hard then i turned of for thurles it was like hitting a wall went down to about 19kph it was like climbing a serious hill then the rain got heavy could bearly see its at times like this that snooker seems like a good sport to get into but you have to take the rough with the smooth and remember "march of many weathers" dont leave the rain gear at home even if its lovely when leaving home.

Raam

Rallymad wrote: »

Give me rain any day. I hate wind. I was out on Wednesday on a 50k spin and I had the wind in my face for the first 20km. Then from Cashel to Two Mile Borris the wind was across me but it was not a problem as I was flying. I really put the hammer down trying to keep the bike speed up to 40kph, pedaling hard. I then turned off for Thurles and it was like hitting a wall. My speed went down to about 19kph. It was like climbing a serious hill. Then the rain got heavy and I could barely see. It's at times like this that snooker seems like a good sport to get into, but you have to take the rough with the smooth and remember "March of many weathers" and don't leave the rain gear at home even if its lovely when leaving home.

FYP, sorry

TheBlaaMan

Lumen wrote: »

24kph before.
28kph after.

That's a 17% improvement in terms of speed.

Fastest time with previous set-up 120 minutes
New time with change in set-up 107 minutes

= 10.8% drop on previous / improvement in time

(accepting your kmph calculation when based on longer 2hr5min )

DirkVoodoo

Yes, wind makes a fricking huge difference, especially when you have the frontal profile of a stop sign (stupid giant head).

Slightly OT, but is "Two mile Borris" an actual place, like different to regular "Borris" (which I know is pronounced Burrrr-is by the locals). Would it not get confusing if you were saying "Oh, I'm two miles from Borris", "Two Mile Borris, why are you there? No what you want to do is look for a man sitting on a wall, take a left, wave at the cows and then continue onto Burrr-is from there".

Lumen

TheBlaaMan wrote: »

Fastest time with previous set-up 120 minutes
New time with change in set-up 107 minutes

= 10.8% drop on previous / improvement in time

Most people would consider a 100% improvement to mean "being twice as good".

By your methods, an 100% improvement would require breaking the speed of light and arriving instantaneously.

Chips Lovell

Borris, Two Mile Borris and Borris In Ossory are all different places.

niceonetom

I'd been thinking about this too - my question was: if you do an out-and-back TT directly along the wind, i.e. pure tailwind for one half and pure headwind for the other, does it cancel out? Does the wind give you back what it takes out of you?

My guess was that no, it doesn't, because you'd spend less time with the tail wind because you're going faster and so the avg speed remains lower than it would be on a still day. Same thing happens with hills - even descending at 80kph won't make up for climbing at 15kph.

The bike calculator agrees:
A 16km TT into and then out of a 30kph wind gives 26.6 minutes (18.9 into the wind, 7.7 tailwind)
Same TT with no wind it gives 23 minutes (which seems a bit optimistic) with both out and back being the same obviously.

DirkVoodoo

el tonto wrote: »

Borris, Two Mile Borris and Borris In Ossory are all different places.

It's the Irish equivalent of "Borough" according to wikipedia.

So confusing, like leaving Dungarvan only to be following signs to Dungarvan, which isn't the same Dungarvan. Or the "red cow roundabout" which foiled me the first time because there is no "red cow" signpost. Just follow the exit numbers, simples!

Lumen

niceonetom wrote: »

I'd been thinking about this too - my question was: if you do an out-and-back TT directly along the wind, i.e. pure tailwind for one half and pure headwind for the other, does it cancel out? Does the wind give you back what it takes out of you?

You're right, wind is bad.

Previous thread.

Raam

Lumen wrote: »

You're right, wind is bad.

Previous thread.

Ah, but it can help make you stronger and that's good.

Rallymad

DirkVoodoo wrote: »

Yes, wind makes a fricking huge difference, especially when you have the frontal profile of a stop sign (stupid giant head).

Slightly OT, but is "Two mile Borris" an actual place, like different to regular "Borris" (which I know is pronounced Burrrr-is by the locals). Would it not get confusing if you were saying "Oh, I'm two miles from Borris", "Two Mile Borris, why are you there? No what you want to do is look for a man sitting on a wall, take a left, wave at the cows and then continue onto Burrr-is from there".

Here is my little route i took voodoo its point D on the map its also the place the new tipperary venue with casino that the goverment have been going on about now you have a heads up on everyone else who didnt know where it was .
http://maps.google.ie/maps?f=d&source=s_d&saddr=thurles&daddr=Holycross+to:Cashel+to:Two+Mile+Borris+to:Thurles&geocode=Fa3QIwMdpLaI_yl9Z9eE6sRcSDGVxcduNDJLBw%3BFaU6IwMdx-uH_ykX8PStxsVcSDHABjKXqccACg%3BFehXIQMdHZeH_yln5SMM6MtcSDHA6TGXqccACg%3BFRS6IwMdrlCK_ylx183bsNtcSDHgkTGXqccACg%3BFa3QIwMdpLaI_yl9Z9eE6sRcSDGVxcduNDJLBw&hl=en&mra=ls&dirflg=h&sll=52.594706,-7.80304&sspn=0.264441,0.883026&ie=UTF8&ll=52.597209,-7.79068&spn=0.132213,0.441513&z=11

Heres another link for you on the casino so you will know more about it

http://www.youtube.com/watch?v=DcxjPazFB2w

el tel

Cycling into a headwind is Crazy thing. If the headwind is 20kmh and you are doing 21 then you only move forward at 1 kmh! Wtf!? One hour to travel one km? Er, no thanks!
And if the wind speed increases...sure you wouldn't even get out of the street ffs. Quite simply unleas you can excced the winds velocity by about 15 kmh you wont get anywhere worth talking about.

Raam

Applied maths for the insane!

oflahero

Raam wrote: »

Rallymad wrote:

even if it's lovely when leaving home

FYP, sorry

FYP, sorry

Raam

oflahero wrote: »

FYP, sorry

Gah, I knew I'd miss at least one!

papac

el tonto wrote: »

Two Mile Borris.

Named after a famous Russian 3000 metre runner.??

I'll get my coat

Keep_Her_Lit

papac wrote: »

Named after a famous Russian 3000 metre runner.??

papac, you are being silly. Two Mile Borris was named after local visionary, sage, taxidermist and all-round dacent skin, Borris McGrath (1822-1889).

Borris was a kindly soul and a vigorous proponent of the old maxim that a person should never judge another before walking a mile in their shoes. Furthermore, when helping anyone in need, which was often, it was well known that Borris always went the extra mile. So on top of the mile after which he never judged anybody, that made two miles.

And so it was upon his sad demise in 1889 that the village’s name was changed to Two Mile Borris. Before that, it had been called Five Furlong Daithí but that’s a story for another day ….

Diego Murphy

Rallymad wrote: »

Give me rain any day hate wind was out wednesday on a 50k spin wind in face for first 20k then cashel to two mile borris wind accross me but not a problem was flying really put the hammer down trying to keep bike up to 40kph peddling hard then i turned of for thurles it was like hitting a wall went down to about 19kph it was like climbing a serious hill then the rain got heavy could bearly see its at times like this that snooker seems like a good sport to get into but you have to take the rough with the smooth and remember "march of many weathers" dont leave the rain gear at home even if its lovely when leaving home.

you're right, rain is manageable and to honest in cycling gear, you can only get so wet. I remember cycling from Cork to Skibbereen one day. Rain was belting down but i had a head wind the whole way there. It was utterly miserable. Would have been ok if i didn't have to contend with the wind.

mloc123

No such thing as a tail wind, just days when you are 'feeling strong'

papac

Keep_Her_Lit wrote: »

.......old maxim that a person should never judge another before walking a mile in their shoes...............

So when you judge 'em you are a mile away and they are barefoot.???

.....coat again........

Keep_Her_Lit

papac wrote: »

So when you judge 'em you are a mile away and they are barefoot.???

.....coat again........

Priceless! You're on good form ...

kincsem

DirkVoodoo wrote: »

Slightly OT, but is "Two mile Borris" an actual place?

It is the place where the big casino isn't (Michael Lowry and all that).

Rallymad

Hopefully it will be there as lots of jobs from it and there badly needed

helimachoptor

Nothing worse than a head wind. Couple of years ago used to cycle from citywest to town on a mtb nomally took 50 mins with the gale that day it took me me 100 mins on the way back it only took 30 and it was so strong I didn't have to do that much cycling:)