Crank Aero Position?

For Roadies

Crank Aero Position?

Postby Downhill » Sun Apr 22, 2012 10:44 pm

Well I've just got to ask...

Does crank position have any significant effect on aero drag?

If so, what's the best position when coasting in a straight line at high speed? 12 O'clock / 6 O'clock, or 9 and 3?
Today's effort = Tomorrows reward.
2010 Oppy C6
Downhill
 
Posts: 353
Joined: Thu Sep 30, 2010 1:11 am
Location: WA

by BNA » Mon Apr 23, 2012 9:50 am

BNA
 

Re: Crank Aero Position?

Postby Alex Simmons/RST » Mon Apr 23, 2012 9:50 am

Do some virtual elevation analysis of coast down tests and you could work it out. Need a good high frequency accurate speed logger (speed every second is just enough, provided speed data is measured to nearest 0.2km/h) and a calm day. And a hill with a flat top approach, downhill section and a flat run off area at bottom is ideal.
User avatar
Alex Simmons/RST
Expert
 
Posts: 3249
Joined: Fri May 02, 2008 3:51 pm

Re: Crank Aero Position?

Postby brentono » Mon Apr 23, 2012 10:08 am

To take a logical approach, and from much observation and a lot of personal experience,
it would have to be 9 and 3!
Cheers
:mrgreen:
Lone Rider- I rode on the long, dark road... before I danced under the lights.
User avatar
brentono
 
Posts: 3667
Joined: Mon Jul 13, 2009 12:33 pm
Location: Perth DubyaEh.

Re: Crank Aero Position?

Postby JV911 » Mon Apr 23, 2012 10:28 am

most of the pros seem to coast at 9 and 3
<---LACC--->
<---BMC SLR01--->

User avatar
JV911
 
Posts: 5451
Joined: Mon Sep 01, 2008 1:22 pm
Location: Sydney, Australia

Re: Crank Aero Position?

Postby DavidI » Tue Apr 24, 2012 8:53 am

My recollection of various magazine articles based on wind tunnel testing is that the best position is, as stated, 9 & 3.
As to whether it has a "significant" effect... well, that depends on what you consider "significant." :wink:
DavidI
 
Posts: 171
Joined: Fri Mar 09, 2012 8:24 am

Re: Crank Aero Position?

Postby foo on patrol » Wed Apr 25, 2012 8:33 am

Keep pedalling softy! :mrgreen: Yep 9/3. :wink:

Foo
I don't suffer fools easily and so long as you have done your best,you should have no regrets.
Goal 6000km
Image
User avatar
foo on patrol
 
Posts: 4036
Joined: Sat Dec 19, 2009 10:12 am
Location: Sanstone Point QLD

Re: Crank Aero Position?

Postby Downhill » Wed Apr 25, 2012 12:56 pm

foo on patrol wrote:Keep pedalling softy! :mrgreen: Yep 9/3. :wink:

Foo


But I've run out of gears!!! :mrgreen: :mrgreen:
Today's effort = Tomorrows reward.
2010 Oppy C6
Downhill
 
Posts: 353
Joined: Thu Sep 30, 2010 1:11 am
Location: WA

Re: Crank Aero Position?

Postby foo on patrol » Wed Apr 25, 2012 3:10 pm

Well try harder! :roll: :lol:

Foo
I don't suffer fools easily and so long as you have done your best,you should have no regrets.
Goal 6000km
Image
User avatar
foo on patrol
 
Posts: 4036
Joined: Sat Dec 19, 2009 10:12 am
Location: Sanstone Point QLD

Re: Crank Aero Position?

Postby hannos » Thu Apr 26, 2012 4:04 pm

JV911 wrote:most of the pros seem to coast at 9 and 3



well they're wrong!

It's 3 and 9!
2010 BMC SLC01
Image
User avatar
hannos
 
Posts: 4002
Joined: Fri Mar 19, 2010 10:18 am
Location: Sydney

Re: Crank Aero Position?

Postby foo on patrol » Sat Apr 28, 2012 5:43 pm

^^ Idiot! ^^ :lol:

Foo
I don't suffer fools easily and so long as you have done your best,you should have no regrets.
Goal 6000km
Image
User avatar
foo on patrol
 
Posts: 4036
Joined: Sat Dec 19, 2009 10:12 am
Location: Sanstone Point QLD

Re: Crank Aero Position?

Postby Downhill » Sat Apr 28, 2012 8:39 pm

hannos wrote:
JV911 wrote:most of the pros seem to coast at 9 and 3



well they're wrong!

It's 3 and 9!


... but only if you're left handed! :mrgreen:
Today's effort = Tomorrows reward.
2010 Oppy C6
Downhill
 
Posts: 353
Joined: Thu Sep 30, 2010 1:11 am
Location: WA


Return to Road Biking

Who is online

Users browsing this forum: flashpixx



Top Bikes & Gear
Torpedo 7 Torpedo7 AU
Cell Bikes Cell Bikes AU
Ground Effect Ground Effect NZ
Ebay Ebay AU
Chain Reaction Cycles CRC UK
Wiggle Wiggle UK
ProBikeKit ProBikeKit UK
Evans Cycles Evans Cycles UK
JensonUSA Jenson USA
JensonUSA Competitive Cyclist