A Cycling & bikes forum. CycleBanter.com

Go Back   Home » CycleBanter.com forum » rec.bicycles » Techniques
Site Map Home Register Authors List Search Today's Posts Mark Forums Read Web Partners

Question for Frank



 
 
Thread Tools Display Modes
  #21  
Old November 1st 16, 03:26 PM posted to rec.bicycles.tech
Frank Krygowski[_2_]
external usenet poster
 
Posts: 7,511
Default Question for Frank

On Tuesday, November 1, 2016 at 7:25:38 AM UTC-4, John B Slocomb wrote:

I have the feeling that there is a matter in definition here. Is
"aero" a term used only for those with their back perfectly flat, or
can it apply to someone that is leaning forward only 45 degrees?

I've found that simply moving my hands to the drops with my elbows
still straight increases coasting speed on one particular kill by just
about 1 kph. Is that not "aero"?


"Aero" is a vague word, of course. But IME moving from the drops to the
aero bar causes a similar increase in speed, perhaps even more.

A few years ago, there were some wind tunnel test results reported in _Bicycle
Quarterly_. Of course, they've appeared in other sources as well - but those
in BQ concentrated on fairly normal-looking bikes, not time trial machines or
the like.

One salient fact was that drag coefficent seemed unaffected by rider posture.
Any aero benefit came (almost?) entirely from reductions in frontal area. If
true, that's good news, because it's far easier to notice one's own changes in
frontal area. It should be obvious, for example, whether one's elbows are
sticking out in the wind or not.

- Frank Krygowski

Ads
  #22  
Old November 2nd 16, 12:15 AM posted to rec.bicycles.tech
John B Slocomb
external usenet poster
 
Posts: 356
Default Question for Frank

On Tue, 1 Nov 2016 07:26:35 -0700 (PDT), Frank Krygowski
wrote:

On Tuesday, November 1, 2016 at 7:25:38 AM UTC-4, John B Slocomb wrote:

I have the feeling that there is a matter in definition here. Is
"aero" a term used only for those with their back perfectly flat, or
can it apply to someone that is leaning forward only 45 degrees?

I've found that simply moving my hands to the drops with my elbows
still straight increases coasting speed on one particular kill by just
about 1 kph. Is that not "aero"?


"Aero" is a vague word, of course. But IME moving from the drops to the
aero bar causes a similar increase in speed, perhaps even more.

A few years ago, there were some wind tunnel test results reported in _Bicycle
Quarterly_. Of course, they've appeared in other sources as well - but those
in BQ concentrated on fairly normal-looking bikes, not time trial machines or
the like.

One salient fact was that drag coefficent seemed unaffected by rider posture.
Any aero benefit came (almost?) entirely from reductions in frontal area. If
true, that's good news, because it's far easier to notice one's own changes in
frontal area. It should be obvious, for example, whether one's elbows are
sticking out in the wind or not.

- Frank Krygowski



But one must shave the legs :-)
  #23  
Old November 2nd 16, 12:21 AM posted to rec.bicycles.tech
Sir Ridesalot
external usenet poster
 
Posts: 5,270
Default Question for Frank

On Tuesday, November 1, 2016 at 7:15:50 PM UTC-4, John B Slocomb wrote:
On Tue, 1 Nov 2016 07:26:35 -0700 (PDT), Frank Krygowski
wrote:

On Tuesday, November 1, 2016 at 7:25:38 AM UTC-4, John B Slocomb wrote:

I have the feeling that there is a matter in definition here. Is
"aero" a term used only for those with their back perfectly flat, or
can it apply to someone that is leaning forward only 45 degrees?

I've found that simply moving my hands to the drops with my elbows
still straight increases coasting speed on one particular kill by just
about 1 kph. Is that not "aero"?


"Aero" is a vague word, of course. But IME moving from the drops to the
aero bar causes a similar increase in speed, perhaps even more.

A few years ago, there were some wind tunnel test results reported in _Bicycle
Quarterly_. Of course, they've appeared in other sources as well - but those
in BQ concentrated on fairly normal-looking bikes, not time trial machines or
the like.

One salient fact was that drag coefficent seemed unaffected by rider posture.
Any aero benefit came (almost?) entirely from reductions in frontal area. If
true, that's good news, because it's far easier to notice one's own changes in
frontal area. It should be obvious, for example, whether one's elbows are
sticking out in the wind or not.

- Frank Krygowski



But one must shave the legs :-)


There was a study done, iirc not that long ago, that showed a pretty good aero asdvantage with shaved legs. In fact those that did the study were surprised at how much of an advantage sghaved legs gave.

Cheers
  #24  
Old November 3rd 16, 04:02 AM posted to rec.bicycles.tech
Joy Beeson
external usenet poster
 
Posts: 1,638
Default Question for Frank

On Tue, 1 Nov 2016 07:26:35 -0700 (PDT), Frank Krygowski
wrote:

"Aero" is a vague word, of course. But IME moving from the drops to the
aero bar causes a similar increase in speed, perhaps even more.


And sitting up straight and spreading yourself out is a good way to
brake when coasting down a hill.

--
Joy Beeson
joy beeson at comcast dot net
http://wlweather.net/PAGEJOY/

  #25  
Old November 3rd 16, 12:30 PM posted to rec.bicycles.tech
John B Slocomb
external usenet poster
 
Posts: 356
Default Question for Frank

On Wed, 02 Nov 2016 23:02:14 -0400, Joy Beeson
wrote:

On Tue, 1 Nov 2016 07:26:35 -0700 (PDT), Frank Krygowski
wrote:

"Aero" is a vague word, of course. But IME moving from the drops to the
aero bar causes a similar increase in speed, perhaps even more.


And sitting up straight and spreading yourself out is a good way to
brake when coasting down a hill.


Yes, I think Frank mentioned that. Downhill speed builds up until the
aerodynamic drag equals the effect of gravity. Based on sky divers
anecdotes that is something like 100 mph. Whoopee!
  #26  
Old November 3rd 16, 01:54 PM posted to rec.bicycles.tech
DATAKOLL MARINE RESEARCH
external usenet poster
 
Posts: 2,011
Default Question for Frank

On Tuesday, November 1, 2016 at 7:21:08 PM UTC-4, Sir Ridesalot wrote:
On Tuesday, November 1, 2016 at 7:15:50 PM UTC-4, John B Slocomb wrote:
On Tue, 1 Nov 2016 07:26:35 -0700 (PDT), Frank Krygowski
wrote:

On Tuesday, November 1, 2016 at 7:25:38 AM UTC-4, John B Slocomb wrote:

I have the feeling that there is a matter in definition here. Is
"aero" a term used only for those with their back perfectly flat, or
can it apply to someone that is leaning forward only 45 degrees?

I've found that simply moving my hands to the drops with my elbows
still straight increases coasting speed on one particular kill by just
about 1 kph. Is that not "aero"?

"Aero" is a vague word, of course. But IME moving from the drops to the
aero bar causes a similar increase in speed, perhaps even more.

A few years ago, there were some wind tunnel test results reported in _Bicycle
Quarterly_. Of course, they've appeared in other sources as well - but those
in BQ concentrated on fairly normal-looking bikes, not time trial machines or
the like.

One salient fact was that drag coefficent seemed unaffected by rider posture.
Any aero benefit came (almost?) entirely from reductions in frontal area. If
true, that's good news, because it's far easier to notice one's own changes in
frontal area. It should be obvious, for example, whether one's elbows are
sticking out in the wind or not.

- Frank Krygowski



But one must shave the legs :-)


There was a study done, iirc not that long ago, that showed a pretty good aero asdvantage with shaved legs. In fact those that did the study were surprised at how much of an advantage sghaved legs gave.

Cheers


those reading the study were surprised how much leverage the advantage gave the study
  #27  
Old November 3rd 16, 04:10 PM posted to rec.bicycles.tech
Frank Krygowski[_4_]
external usenet poster
 
Posts: 10,538
Default Question for Frank

On 11/3/2016 7:30 AM, John B Slocomb wrote:
On Wed, 02 Nov 2016 23:02:14 -0400, Joy Beeson
wrote:

On Tue, 1 Nov 2016 07:26:35 -0700 (PDT), Frank Krygowski
wrote:

"Aero" is a vague word, of course. But IME moving from the drops to the
aero bar causes a similar increase in speed, perhaps even more.


And sitting up straight and spreading yourself out is a good way to
brake when coasting down a hill.


Yes, I think Frank mentioned that. Downhill speed builds up until the
aerodynamic drag equals the effect of gravity. Based on sky divers
anecdotes that is something like 100 mph. Whoopee!


It depends on the slope, of course (and wind direction, to a much lesser
degree). And weight of the bike+rider.

I led a fairly hilly club ride last week. Using my aero bars on the
downhills, I generally out-coast most members of our club. But one new
member of our club was blasting past me on every downhill, despite
sitting upright and using straight handlebars. His secret? I suspect he
weighs over 250 pounds.

(I give him great credit for keeping up on the uphills!)


--
- Frank Krygowski
  #28  
Old November 4th 16, 12:26 AM posted to rec.bicycles.tech
John B Slocomb
external usenet poster
 
Posts: 356
Default Question for Frank

On Thu, 3 Nov 2016 11:10:56 -0400, Frank Krygowski
wrote:

On 11/3/2016 7:30 AM, John B Slocomb wrote:
On Wed, 02 Nov 2016 23:02:14 -0400, Joy Beeson
wrote:

On Tue, 1 Nov 2016 07:26:35 -0700 (PDT), Frank Krygowski
wrote:

"Aero" is a vague word, of course. But IME moving from the drops to the
aero bar causes a similar increase in speed, perhaps even more.

And sitting up straight and spreading yourself out is a good way to
brake when coasting down a hill.


Yes, I think Frank mentioned that. Downhill speed builds up until the
aerodynamic drag equals the effect of gravity. Based on sky divers
anecdotes that is something like 100 mph. Whoopee!


It depends on the slope, of course (and wind direction, to a much lesser
degree). And weight of the bike+rider.

I led a fairly hilly club ride last week. Using my aero bars on the
downhills, I generally out-coast most members of our club. But one new
member of our club was blasting past me on every downhill, despite
sitting upright and using straight handlebars. His secret? I suspect he
weighs over 250 pounds.

(I give him great credit for keeping up on the uphills!)


Yes, weight certainly does help in the mountains. About half the time
:-)
  #29  
Old November 4th 16, 04:13 PM posted to rec.bicycles.tech
Radey Shouman
external usenet poster
 
Posts: 1,747
Default Question for Frank

John B Slocomb writes:

On Thu, 3 Nov 2016 11:10:56 -0400, Frank Krygowski
wrote:

On 11/3/2016 7:30 AM, John B Slocomb wrote:
On Wed, 02 Nov 2016 23:02:14 -0400, Joy Beeson
wrote:

On Tue, 1 Nov 2016 07:26:35 -0700 (PDT), Frank Krygowski
wrote:

"Aero" is a vague word, of course. But IME moving from the drops to the
aero bar causes a similar increase in speed, perhaps even more.

And sitting up straight and spreading yourself out is a good way to
brake when coasting down a hill.

Yes, I think Frank mentioned that. Downhill speed builds up until the
aerodynamic drag equals the effect of gravity. Based on sky divers
anecdotes that is something like 100 mph. Whoopee!


It depends on the slope, of course (and wind direction, to a much lesser
degree). And weight of the bike+rider.

I led a fairly hilly club ride last week. Using my aero bars on the
downhills, I generally out-coast most members of our club. But one new
member of our club was blasting past me on every downhill, despite
sitting upright and using straight handlebars. His secret? I suspect he
weighs over 250 pounds.

(I give him great credit for keeping up on the uphills!)


Yes, weight certainly does help in the mountains. About half the time
:-)


Half the *distance* you mean. Way less than half the *time*.


--
  #30  
Old November 5th 16, 12:57 AM posted to rec.bicycles.tech
John B Slocomb
external usenet poster
 
Posts: 356
Default Question for Frank

On Fri, 04 Nov 2016 11:13:58 -0400, Radey Shouman
wrote:

John B Slocomb writes:

On Thu, 3 Nov 2016 11:10:56 -0400, Frank Krygowski
wrote:

On 11/3/2016 7:30 AM, John B Slocomb wrote:
On Wed, 02 Nov 2016 23:02:14 -0400, Joy Beeson
wrote:

On Tue, 1 Nov 2016 07:26:35 -0700 (PDT), Frank Krygowski
wrote:

"Aero" is a vague word, of course. But IME moving from the drops to the
aero bar causes a similar increase in speed, perhaps even more.

And sitting up straight and spreading yourself out is a good way to
brake when coasting down a hill.

Yes, I think Frank mentioned that. Downhill speed builds up until the
aerodynamic drag equals the effect of gravity. Based on sky divers
anecdotes that is something like 100 mph. Whoopee!

It depends on the slope, of course (and wind direction, to a much lesser
degree). And weight of the bike+rider.

I led a fairly hilly club ride last week. Using my aero bars on the
downhills, I generally out-coast most members of our club. But one new
member of our club was blasting past me on every downhill, despite
sitting upright and using straight handlebars. His secret? I suspect he
weighs over 250 pounds.

(I give him great credit for keeping up on the uphills!)


Yes, weight certainly does help in the mountains. About half the time
:-)


Half the *distance* you mean. Way less than half the *time*.


Well, I suppose I was using the vernacular, i.e., the time I was in
Belgrade, or the time I saw that ugly woman, or even the time I was in
the mountains :-)

 




Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

vB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
Question for Frank John B. Techniques 4 May 3rd 15 04:26 AM
Question for Frank John B. Techniques 11 October 20th 12 01:53 AM
Let's be Frank.... Anton Berlin Racing 3 October 30th 09 01:00 AM
Where's Dr. Frank? MagillaGorilla[_3_] Racing 0 September 25th 08 09:35 PM
Frank Andre Racing 1 October 16th 06 07:31 AM


All times are GMT +1. The time now is 03:54 PM.


Powered by vBulletin® Version 3.6.4
Copyright ©2000 - 2024, Jelsoft Enterprises Ltd.
Copyright ©2004-2024 CycleBanter.com.
The comments are property of their posters.