The importance of crank length to the cyclist.

[Boeing]

That's what happens when one offers anecdotes as proof of ones position rather than actual evidence.

Martin, every person's pathologies are unique. My top three causes of lower body injuries in cyclists are based on a review of the cycling injury literature that appears to run counter to Frank's top two. Glad you found a solution. The solution to my lower body issues is a double hip replacement.

ok coach google

 

[coapman]

You may not know for sure - but myself and the expert fitter (also a sports physiologist) that made the assessment and determined the cause and solution do.

The person that did my fitting is able to point to before and after analysis to show what part of my pedalling action caused the irritation and that the changes that have been made have not only avoided that irritation but also allowed me to produce more power with less effort.

CoachFergie is the coach who claims pedaling action is of no importance ?

 

[acoggan]

CoachFergie is the coach who claims pedaling action is of no importance ?

Coapman, the troll also known as perfection?

 

[acoggan]

So much for the rational discussion we were having.

There is nothing rational about pontificating endlessly based a case study of unknown quality while completely ignoring the large amount of data already collected by those with a far better understanding of the topic at hand (case-in-point: your incorrect speculation that widening the distance between the legs will reduce aerodynamic drag).

 

[coapman]

Coapman, the troll also known as perfection?

Also known as N Crowley on CyclingForums, no troll, it is fact. I could have included you along with CoachFergie, especially when the topic of cycling related lower back pain is involved. BrimBros PM, when it becomes available, will confirm my claim of maximal torque through 12 o'c is genuine.

 

[CoachFergie]

Yawn. Force measuring pedals have been around for a good 30 years or more as has been your chance to prove your opinion on pedalling.

 

[acoggan]

As a public service announcement, below are some of the studies Frank could have consulted before performing his experiment. If he had done so, he would have realized that he was really just wasting his (client's?) time comparing a road helmet to just one aero helmet, and instead could have used it to find the aero helmet that worked best for that individual.


1. Kyle CR (1989). The aerodynamics of helmets and handlebars. Cycling Sci 1: 122–125.

2. Chin KY, Lim LK (2001). The design of an aerodynamically sound biker’s helmet. Department of Mechanical Engineering, University of Adelaide, Adelaide.

3. Blair K, Sidelko S (2008). Aerodynamic performance of cycling time trial helmets. In: Estivalet M, Brisson P, eds. The Engineering of Sport 7, New York: Springer, pp. 371-377.

4. Chabroux V, Barelle C, Favier D (2008). Aerodynamics of time trial cycling helmets. In: Estivalet M, Brisson P, eds. The Engineering of Sport 7, New York: Springer, pp. 401-410.

5. Brownlie L, Ostafichukb P, Tews E, Muller H, Brigg E, Franks K (2010). The wind-averaged aerodynamic drag of competitive time trial cycling helmets. Procedia Eng 2: 2419–2424.

6. Chabroux V, Nsi Mba M, Sainton P, Favier D (2010). Wake characteristics of time trial helmets using PIV-3C technique. 15th Int Symp on Applications of Laser Techniques to Fluid Mechanics. Lisbon, Portugal, 05-08 July, 2010

 

[coapman]

Yawn. Force measuring pedals have been around for a good 30 years or more as has been your chance to prove your opinion on pedalling.

Not in this country, I don't like the inconvenience of travelling with equipment. Question, does leverage take effect in the rear sprocket when chain power is transferred to the cogs.

 

[CoachFergie]

Not in this country, I don't like the inconvenience of travelling with equipment. Question, does leverage take effect in the rear sprocket when chain power is transferred to the cogs.

Saddest excuse ever. Your opinion has been duly noted

 

[coapman]

Saddest excuse ever. Your opinion has been duly noted

You are the coach but you never give an answer to my questions. It appears that Martin's crank length facts are based on 4 second sprint data. Sprinting is not time trialing and there was no mention of techniques used. For you to get the same torque from one pedal stroke while using the same crank length, rear sprocket and cadence as that which can be got from the perfect TT stroke, I estimate you would have to double your chain ring size. Would varying crank lengths make a significant difference in that case?

 

[Ripper]

Wow

I had a look to see if this thread would be interesting. But there is a lot of silliness going on!

Now I need to run off to the dollar store to buy me some 100 mm cranks

 

[coapman]

I had a look to see if this thread would be interesting. But there is a lot of silliness going on!

Now I need to run off to the dollar store to buy me some 100 mm cranks

Silly was the word used by cycling experts in their description of triathletes who were using aerobars a few short years ago.

 

[coapman]

Now I need to run off to the dollar store to buy me some 100 mm cranks

A more precise increase required would be 84%.

 

[Ripper]

Silly was the word used by cycling experts in their description of triathletes who were using aerobars a few short years ago.

Bwa ha ha ha. Bah! Perhaps by traditionalists, but many an expert knew they would be an improvement. There was no real debate in the scientific community as there was evidence, even at the time, of the benefit.

 

[CoachFergie]

Bwa ha ha ha. Bah! Perhaps by traditionalists, but many an expert knew they would be an improvement. There was no real debate in the scientific community as there was evidence, even at the time, of the benefit.

It was an easy theory to test and unlike the Italian TTT or Thierry Marie in 1986, the Hour record, or anything to do with Graeme Obree the UCI didn't see fit to intervene.

 

[Ripper]

It was an easy theory to test and unlike the Italian TTT or Thierry Marie in 1986, the Hour record, or anything to do with Graeme Obree the UCI didn't see fit to intervene.

That was basically my point.

Ah, the good old UCI. They really did not like Obree's innovations, did they? Lucky for us he did not "create" aero bars or they would have been banned as well

 

[coapman]

There was no real debate in the scientific community as there was evidence, even at the time, of the benefit.

The same applies to Anquetil's TT pedal stroke but of course unlike the use of aero bars, it could not be copied. By copying the triathletes and their arm rest aero bars, scientists made another serious error because with the use of such bars, any hope of someone else discovering the ideal TT pedaling technique vanished. The ideal and safer aero bars are ' Scott Rake ' type which retain the natural racing body position. Back to crank length: After further consideration I now believe the increase in chain ring size necessary to balance torque output from the natural and ideal tt techniques should be between 50 and 70 %. This increase is required for one to almost double torque in the 2-4 o'c sector which should compensate for the inability to apply max torque between 11-1 o'c (twice per revolution), and to also double torque application between 1-2 o'c. How would a 145 crank cope with such power output.

 

[CoachFergie]

The same applies to Anquetil's TT pedal stroke but of course unlike the use of aero bars, it could not be copied. By copying the triathletes and their arm rest aero bars, scientists made another serious error because with the use of such bars, any hope of someone else discovering the ideal TT pedaling technique vanished. The ideal and safer aero bars are ' Scott Rake ' type which retain the natural racing body position. Back to crank length: After further consideration I now believe the increase in chain ring size necessary to balance torque output from the natural and ideal tt techniques should be between 50 and 70 %. This increase is required for one to almost double torque in the 2-4 o'c sector which should compensate for the inability to apply max torque between 11-1 o'c (twice per revolution), and to also double torque application between 1-2 o'c. How would a 145 crank cope with such power output.

Ha ha, what a vivid imagination you have.

 

[Ripper]

By copying the triathletes and their arm rest aero bars, scientists made another serious error because with the use of such bars, any hope of someone else discovering the ideal TT pedaling technique vanished.

???? Not sure your logic with this?

The ideal and safer aero bars are ' Scott Rake ' type which retain the natural racing body position.

Ummmmmm, no.

Back to crank length: After further consideration I now believe the increase in chain ring size necessary to balance torque output from the natural and ideal tt techniques ...

Are you smoking somethin'?

 

[Boeing]

Yawn. Force measuring pedals have been around for a good 30 years or more as has been your chance to prove your opinion on pedalling.

does the word "dogmatic" mean anything to you?

 

[coapman]

???? Not sure your logic with this?

Application of maximal torque through 12 o'c needs independent resistance, the arms supply this, but they cannot do it when they are effectively idling on their rests.

 

[coapman]

Ha ha, what a vivid imagination you have.

What prevents the extra leverage of longer cranks from improving performance ?

 

[Martin318is]

Application of maximal torque through 12 o'c needs independent resistance, the arms supply this, but they cannot do it when they are effectively idling on their rests.

but the rider's hands are holding the extensions. There is plenty of opportunity to prodive resistance through that hand position so I dont really see how this causes a loss of the ideal TT position..

 

[Ripper]

but the rider's hands are holding the extensions. There is plenty of opportunity to prodive resistance through that hand position so I dont really see how this causes a loss of the ideal TT position..

It wouldn't. I am not sure if Coapman is doing some manner of trolling, or if he/she simply does not understand.

 

[CoachFergie]

Noel has been spouting his opinion for the last several years. Based on what he observes from the video footage of Jacques Anquetil. Never supplied any data. Force measuring pedals have been available for decades and any data that a change in force application around the pedal stroke being of any benefit has yet to be found.

Bit like the claimed importance of crank length.

Asker Juekendrup wrote a paper on where to spend your money to really maximise your performance.

http://www.cyclesportcoaching.com/Files/HowToSpendMoney.pdf