"against the wind"
#1
brother's keeper
Thread Starter
Join Date: Nov 2006
Location: ill-adelphia
Posts: 115
Bikes: Ross Carrera, Cayne Uno, Surly Steamroller
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Likes: 0
Liked 0 Times
in
0 Posts
"against the wind"
Any of you that have ridden in the ill-adel the past couple of days have probably encountered the joys of the 50mph winds in yo face... as with any headwind of relative strength, rider's gotta stand up and mash with a smile or else the wind, wins and we cant have that. I experienced this more than I care to recall when i was nestled in chi-town as well, (obviously). Similarly the rider must respond in kind on all of the various hills and climbs we may encounter. So... i contemplated then, and considered again recently, the parallels of the two situations. Might any of you thinking men know of an equation that assimilates the MPH's of the wind gusts with the grade of inclination on a climb? also... feel free to respond with any wind stories/issues/discoveries/solutions you may have?
"you dont need a weather man to know which way the wind blows"
-Dylan
"you dont need a weather man to know which way the wind blows"
-Dylan
#4
F'ing A
Join Date: Oct 2007
Location: SJ
Posts: 321
Bikes: 08 tommaso augusta, 88 specialized sirrus, random cruisers and stuff
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Likes: 0
Liked 0 Times
in
0 Posts
If there is an equation its going to have to factor in how wide you are, what your wearing, etc. It would be cool to know though. I'm going to throw out a guess and say that every mile an hour of headwind equals 1 percent more effort.
#5
Senior Member
Join Date: Sep 2006
Location: Van BC
Posts: 3,744
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Likes: 0
Liked 1 Time
in
1 Post
Yeah the problem with the ops question is how variable your aerodymanic profile can be. A good time trialer in a teardrop helmet with nice aero wheels is going to be much different from a typical bfssfg member in street clothes and back at 45+ degrees to the ground. It would be cool to see a ballpark figure though so I'll watch this space.
#6
Junior Member
Join Date: Feb 2008
Location: Philly
Posts: 22
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Likes: 0
Liked 0 Times
in
0 Posts
I went for a bike ride last night at around 4am in center city...the wind almost brought me to a dead stop a few times.
#8
cab horn
Join Date: Jun 2004
Location: Toronto
Posts: 28,353
Bikes: 1987 Bianchi Campione
Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
Quoted: 42 Post(s)
Likes: 0
Liked 26 Times
in
19 Posts
https://www.exploratorium.edu/cycling/aerodynamics1.html
Yes, it's not a comprehensive calculator. But its good enough to make a point.
15mph cycling into a 0mph headwind = 94w
15mph cycling into a 1mph headiwnd = 108w
15mph cycling into a 2mph headiwnd = 125w
15mph cycling into a 3mph headiwnd = 142w
Looks non-linear to me.
#10
Look at all these buttons
Join Date: Oct 2007
Posts: 984
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Likes: 0
Liked 0 Times
in
0 Posts
Wind with regard to power that needs to be used is a curve.
This is why racing aircraft like the mustang which cruises easily at 270kts add huge engines to their aircraft AND clip the wings/sink rivets/smooth the canopy etc etc etc.
This is also why propeller aircraft are essentially limited to 450mph.
Obviously no one is going that fast on a bike here except for me haha. But its easier to exhibit looking at the top end of the graph.
This is why racing aircraft like the mustang which cruises easily at 270kts add huge engines to their aircraft AND clip the wings/sink rivets/smooth the canopy etc etc etc.
This is also why propeller aircraft are essentially limited to 450mph.
Obviously no one is going that fast on a bike here except for me haha. But its easier to exhibit looking at the top end of the graph.
#13
dig dig dig
Join Date: Jan 2006
Location: Chicago
Posts: 878
Bikes: Full Fendered Bareknuckle, Faggin with 10spd Centaur, 1973 Raleigh 3spd Cruiser.
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Likes: 0
Liked 0 Times
in
0 Posts
I've been brought to a dead stop before from wind. It was eerie too, cause the streets were wet and I could literally see the gust coming at me.
#15
dig dig dig
Join Date: Jan 2006
Location: Chicago
Posts: 878
Bikes: Full Fendered Bareknuckle, Faggin with 10spd Centaur, 1973 Raleigh 3spd Cruiser.
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Likes: 0
Liked 0 Times
in
0 Posts
I hate wind about half the time.
#16
Sausage King
Join Date: Feb 2008
Posts: 150
Bikes: 2008 Specialized Langster, Kilo WT, 1986 Dahon Classic Folder, 1986 Panasonic Mountain Cat
Mentioned: 14 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Likes: 0
Liked 0 Times
in
0 Posts
60% of the time, I hate Bob Seger all the time.
#17
aka mattio
i received an offer to borrow a HED wheelset - HED3 front, disc rear - for the races at VeloCity today. Why oh why was it so windy?! i had to turn down the offer!
#18
FREE DEATHHARE
Join Date: Jul 2007
Location: princeton, nj
Posts: 302
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Likes: 0
Liked 0 Times
in
0 Posts
Rolling through Wyoming and Kansas the wind almost blew me into the ground and at times I could only stop and walk. Times like those I would try and be as aero as possible, so ditch the baggy clothes, use the drops, zip everything up and it makes a big difference.
__________________
transam '07
transam '07
#19
Senior Member
Join Date: Oct 2007
Location: funky town
Posts: 112
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Likes: 0
Liked 0 Times
in
0 Posts
#21
Senior Member
Join Date: Jun 2003
Location: Atlanta
Posts: 1,155
Bikes: Zeus (Razesa) tarck, Giant TCR road, Eddy Merckx road, Fuji Touring Series IV for everything else
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Likes: 0
Liked 0 Times
in
0 Posts
We've established that the graph of the power required to overcome a 1mph increase in wind speed is non-linear.
I would assume that the graph of the power required to overcome an x deg. difference in gradient is also non-linear. Or it may be linear up to a certain point, but at 91 deg (just past vertical), the power required (provided you can stick to the road) will be less than at 90 deg, so the graph will begin to drop.
The problem here is that for a body facing wind resistance, more resistance can always be countered by more power (the graph will keep going up to infinity) provided that the body can endure the forces applied.
So, in general, the graphs cannot be the same so there cannot be an equation that shows a useful relationship between the two for any variables x, y (x,y : neg. Infin.< x,y < Infin. ).
What we would need to do it focus in on a small part of each graph. Say 0 to 45 deg of inclination and 0 to 75mph air velocity (bike velocity + wind velocity in an opposing direction). Then we have to add mass and frontal surface area to both equations. Starts to feel awfully sticky to me. Maybe this is a case where anecdotal evidence is the most useful. i.e. ask an old cyclist.
I would assume that the graph of the power required to overcome an x deg. difference in gradient is also non-linear. Or it may be linear up to a certain point, but at 91 deg (just past vertical), the power required (provided you can stick to the road) will be less than at 90 deg, so the graph will begin to drop.
The problem here is that for a body facing wind resistance, more resistance can always be countered by more power (the graph will keep going up to infinity) provided that the body can endure the forces applied.
So, in general, the graphs cannot be the same so there cannot be an equation that shows a useful relationship between the two for any variables x, y (x,y : neg. Infin.< x,y < Infin. ).
What we would need to do it focus in on a small part of each graph. Say 0 to 45 deg of inclination and 0 to 75mph air velocity (bike velocity + wind velocity in an opposing direction). Then we have to add mass and frontal surface area to both equations. Starts to feel awfully sticky to me. Maybe this is a case where anecdotal evidence is the most useful. i.e. ask an old cyclist.