The pedaling technique thread

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Apr 21, 2009
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Don't waste our time Noel.

Do you actually ride Noel, have you actually tried this. I have tried as you described, within the constraints of the UCI bike fitting regs and it is less powerful and less efficient.

If you actually had the balls to put your money where your mouth is and test your claims you would see how wrong you are.
 
Re: Re:

backdoor said:
CoachFergie said:
So you keep saying Noel, but without data you can't actually prove anything you claim. You are deluded. You cling to this illusion of the perfection of one rider who lets face it, admitted he took drugs and clearly was the best rider of his time. Jacques lucked in and was born with the best VO2max, fractional utilisation of VO2 and efficiency of the day.

Jim Martin has provided a wealth of data that any form of equipment that claims to alter pedalling technique and special methods claimed to improve technique are mostly bogus and any potential gains are so small that even David Brailsford would not be impressed.

Personally, I have tried your method as described by you within the constraints of UCI rules for road cycling and time trial cycling and it is less powerful and far less efficient.
If you are so sure of your methods, why don't you just supply some data as everybody asks. You can't. You sound like a badly broken record
When applying crank torque, at any instant how many teeth of a 52t chainring are involved in pulling the chain or how many degrees of any chainring are involved ?
 
Nov 25, 2010
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Re: Re:

backdoor said:
...
When applying crank torque, at any instant how many teeth of a 52t chainring are involved in pulling the chain or how many degrees of any chainring are involved ?
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From an engineering view (not pedalling technique), the answer depends highly on how the chain and chainring have worn - and that depends of how precisely the dimensions of the chain's pitch and the chainring's teeth have been manufactured. If there is any dimensional variance in those dimensions, then the tooth and link that has the 'tightest' contact will do the pulling - until some other tooth link that has tighter contact comes along.

I think that typically the tightest contact of a tooth/link is when a roller of a link first becomes seated into the 'valley' between teeth. After that point the chain's 'stretch/wear' causes that link to lose tight contact with the tooth as the next link comes along. So probably, ONE tooth at a time does the majority of pulling - and for somewhat less than 360/52 degrees.

Jay Kosta
Endwell NY USA
 
Jun 4, 2015
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Re: Re:

veganrob said:
[quote="[

If you are so sure of your methods, why don't you just supply some data as everybody asks. You can't. You sound like a badly broken record
What type of data, you can either apply additional maximal torque through TDC and 1 o'c or you can't, it's as simple as that.
 
Re: Re:

backdoor said:
veganrob said:
[quote="[

If you are so sure of your methods, why don't you just supply some data as everybody asks. You can't. You sound like a badly broken record
What type of data, you can either apply additional maximal torque through TDC and 1 o'c or you can't, it's as simple as that.
There are ways to measure maximal torque with your pedalling style to see if it is better. Why don't you use those methods along with a video to prove your point. Should be easy.
 
Nov 25, 2010
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Re: Re:

backdoor said:
... But pedalling technique can be very relevant where wearing and stretching of the chain is concerned,
---
Pedalling technique might affect the wear pattern on the CHAINRING.
Increased wear in the ring sectors (relative to the crank arm) at 3 and 9 oc would indicate increased torque being applied at 3 and 9 (relative to standard clockface). If identical ring wear occured at 6 and 12, that would indicate that similar torqued was being applied at 6 and 12. I don't know if anyone has done a good analysis of chainring wear patterns. You can examine YOUR chainring by using the round shank of drill bits to measure the size of the valleys between ring teeth to determine the size and location of wear. Probaby 3 drill sizes would be adequate - largest would indicate location of greatest torque, medium, and smallest. Relative to chankarm, check at 12&6, 3&9, 4:30&10:30, and 1:30&7:30.

Chain wear/stretch is NOT relevant because which chain links bear against the ring is constantly changing, and ALL links will wear at the same rate.

Jay Kosta
Endwell NY USA
 
Nov 25, 2010
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I did try measuring the chainring on my bike, but results were inconclusive. The 3/8inch bit wouldn't fit in any of the valleys, and the 23/64 fit in all - but it seems like some were 'looser' than others. This was done on the large chainring, I changed the inner ring several years ago and do not recall if I changed the orientation of the outer ring at that time ???

I also inspected the old inner ring and it is also difficult to measure. But there seems to be a noticeable visual difference in the 'shark tooth' wear pattern around the ring - And I don't know what the orientation of that ring was on the crank.

Perhaps with an 'inspection magnifier' and a measuring grid, a more exact determination of the wear could be established. I am confident that the teeth around the ring do NOT wear evenly, so the amount of wear could be a meaningful indicator of what sections of the ring contribute most to the crank torque.

Jay Kosta
Endwell NY USA
 
Mar 13, 2013
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Re:

JayKosta said:
I did try measuring the chainring on my bike, but results were inconclusive. The 3/8inch bit wouldn't fit in any of the valleys, and the 23/64 fit in all - but it seems like some were 'looser' than others. This was done on the large chainring, I changed the inner ring several years ago and do not recall if I changed the orientation of the outer ring at that time ???

I also inspected the old inner ring and it is also difficult to measure. But there seems to be a noticeable visual difference in the 'shark tooth' wear pattern around the ring - And I don't know what the orientation of that ring was on the crank.

Perhaps with an 'inspection magnifier' and a measuring grid, a more exact determination of the wear could be established. I am confident that the teeth around the ring do NOT wear evenly, so the amount of wear could be a meaningful indicator of what sections of the ring contribute most to the crank torque.

Jay Kosta
Endwell NY USA
You should first measure a new ring, to see if they're even. If a new ring isn't even, measuring a used ring isn't meaningful.

You should also skip the teeth that are ramped for changing gears. They'll wear differently because the chain will be askew on those teeth when changing gears, and the links might not line up in length 100%.

The ramps can be slotted or pinned in the ring, and can be assisted by teeth of varied height and thickness. Inspect your ring closely to mark the teeth that are expected to wear differently.

When changing gears, half the chain is on the inner ring (say 39 tooth), and half on the outer (say 53 tooth), so the inner ring will experience 53:39 more torque per tooth than the outer when changing.

Also note that on a 10 tooth ring, 5 teeth are always engaged. On a 50 tooth ring, 25. You cannot wear just one tooth.
 
Nov 25, 2010
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The chainrings that I inspected are 'old style' aluminum rings of 1970's vintage, so they are different from modern rings. I don't know what the expected wear pattern on modern rings would be, but I expect that the sectors of greatest wear would be where most torque was being produced.

If you hold the bike stationary and apply pressure to a pedal, you'll find that very few links are actually being held tightly against the chainring. At any instant, only a few links are being 'worked', the others are just being moved around with little contact pressure.

Jay Kosta
Endwell NY USA
 
Jun 4, 2015
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Re:

JayKosta said:
The chainrings that I inspected are 'old style' aluminum rings of 1970's vintage, so they are different from modern rings. I don't know what the expected wear pattern on modern rings would be, but I expect that the sectors of greatest wear would be where most torque was being produced.

If you hold the bike stationary and apply pressure to a pedal, you'll find that very few links are actually being held tightly against the chainring. At any instant, only a few links are being 'worked', the others are just being moved around with little contact pressure.

Jay Kosta
Endwell NY USA
Answer from a question and answer type of forum;

"Depends how well the chain and chainring mesh. Assuming perfect alignment, exactly half the teeth are engaged.

In the real world, the chain will be somewhat elongated. So your worst case is one single tooth is taking all the strain. At this point, wear is accelerated."

Do you know where exactly in the 360 deg. chainring circle this one tooth would be positioned when taking the strain.
 
Nov 25, 2010
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Re: Re:

backdoor said:
... Do you know where exactly in the 360 deg. chainring circle this one tooth would be positioned when taking the strain.
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I don't KNOW exactly where, but my view is that it would be at the position where the chainline is tangent to the chainring - slightly before TDC because of the angle of the chainline from the rear sprocket to the ring.

Jay Kosta
Endwell NY USA
 
Jun 4, 2015
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Re: Re:

JayKosta said:
backdoor said:
... Do you know where exactly in the 360 deg. chainring circle this one tooth would be positioned when taking the strain.
---------------------
I don't KNOW exactly where, but my view is that it would be at the position where the chainline is tangent to the chainring - slightly before TDC because of the angle of the chainline from the rear sprocket to the ring.

Jay Kosta
Endwell NY USA

That would mean another marginal efficiency gain for Anquetil's special TT technique.
 
Jun 4, 2015
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Re: Re:

backdoor said:
JayKosta said:
backdoor said:
... Do you know where exactly in the 360 deg. chainring circle this one tooth would be positioned when taking the strain.
---------------------
I don't KNOW exactly where, but my view is that it would be at the position where the chainline is tangent to the chainring - slightly before TDC because of the angle of the chainline from the rear sprocket to the ring.

Jay Kosta
Endwell NY USA

That would mean another marginal efficiency gain for Anquetil's special TT technique.
Not so , using chain tension testing there are at least 19 teeth engaged on my used chainring and chain but it's hard to get the answer.
 
Nov 25, 2010
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Re: Re:

backdoor said:
... Not so , using chain tension testing there are at least 19 teeth engaged on my used chainring.
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What was the position of the crankarm for your testing?

Jay Kosta
Endwell NY USA
 
Apr 21, 2009
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Yawn, more bullsniz to hide the fact you haven't actually tested your theory, coached someone to do this and reported the results, and taken up the offer to prove your claims in a biomechanics lab. We have tried your theory within the constraints of the current allowed time trial technology and there is reduced power and greatly reduced efficiency!

Provide the evidence Noel, waffle about chain wear and tug of war proves nothing.
 
Nov 25, 2010
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I checked the chain on the 52T ring, and the chain seemed tight against the ring about the same as you mentioned. The ring is old and probably quite worn, the chain is relatively new (so no telling how it fits the worn teeth). On the tight section, I couldn't determine where the chain rollers were pressing firmly against the ring's teeth - or just being pulled tight between the teeth.

I think the question of 'which teeth do the most pulling?' is determined by the wear of the teeth and chain. Detailed inspection of the wear on a new ring and chain, would give the best information.

Jay Kosta
Endwell NY USA
 
Jun 4, 2015
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Re:

JayKosta said:
I checked the chain on the 52T ring, and the chain seemed tight against the ring about the same as you mentioned. The ring is old and probably quite worn, the chain is relatively new (so no telling how it fits the worn teeth). On the tight section, I couldn't determine where the chain rollers were pressing firmly against the ring's teeth - or just being pulled tight between the teeth.

I think the question of 'which teeth do the most pulling?' is determined by the wear of the teeth and chain. Detailed inspection of the wear on a new ring and chain, would give the best information.

Jay Kosta
Endwell NY USA
That question arose as I was trying to figure out if applying max torque at 12 o'c had the same effect on friction at BB ball bearings as when applying it at 3 o'c.
 
Nov 25, 2010
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Re: Re:

backdoor said:
... That question arose as I was trying to figure out if applying max torque at 12 o'c had the same effect on friction at BB ball bearings as when applying it at 3 o'c.
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I don't think that pedalling techique has any perceivable affect on BB ball bearing wear. The balls and contact surfaces are hard steel, and as long as the BB is lubricated and isn't contaminated with abrasive particles the actual 'wear' would be extremely small. The bearings in wheels and headset do experience a lot of 'impact shock', so it's common to find damage from that.

Jay Kosta
Endwell NY USA
 
Jun 4, 2015
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CoachFergie said:
Yawn, more bullsniz to hide the fact you haven't actually tested your theory, coached someone to do this and reported the results, and taken up the offer to prove your claims in a biomechanics lab. We have tried your theory within the constraints of the current allowed time trial technology and there is reduced power and greatly reduced efficiency!

Provide the evidence Noel, waffle about chain wear and tug of war proves nothing.
" The initiation of the pedal cycle starts with the gluteals, taking the hip
from a flexed position at TDC through the power phase to an extended
position. Then at approximately 3 o'clock in the pedal cycle the quadriceps
kick in to take the knee from it's flexed position to an extended position
at BDC.

The rectus femoris is one of the four quadricep muscles, but the only one
to cross both the hip and knee joint, giving it duel responsibility of hip
flexion and knee extension. The quadriceps work in close partnership with
the gluteals (maximus), these are two large powerful groups of muscles
that produce the greatest amount of torque in cycling.

The main role of the hamstrings is knee flexion but they also assist hip
extension. During cycling depending on the position that is adopted by the
cyclist if on an upright bike, the ischial tuberosities may take most of
the load through the saddle therefore compressing the origin of the
hamstrings. The hamstrings main role in cycling is to assist the knee
flexion up through the back part of the pedal stroke but they also play an
important part in stabilising the knee through BDC.

Further down the chain into the lower leg the gastrocnemius and soleus
haven't been found to add much power to the pedal stroke but their main
role is to stabilise the lower leg to enable an efficient transition of the
force generated by the upper leg to the pedal. "
-------------------------------------------------------------------------------------------

Above you have a good description of how you and all natural pedallers power their cranks, the important paragraph there is the last one because it means you use your lower leg for almost the same purpose as Alex S uses his prosthesis, leaving its muscles effectively idling around the pedalling circle. While it's twenty years since I discovered the explanation for Anquetil's sustainable constant high gear power in TT's, which was the ability to make maximal use of his lower leg muscles around TDC and beyond, because I am not a physiologist, it's been only in the last few weeks that I became aware of what makes this technique so effective. The soleus muscle in the lower leg is not only more powerful than the glute or quad muscles but it is also highly fatigue resistant and ideal for the endurance required for constant high gear power output in TT's, it has about 20 % more slow twitch muscle fibre content than the glutes or quads. The soleus produced over half of Anquetil's power from each pedal stroke in TT's . The powerful sport of INDOOR Tug o' War demonstrates what power the soleus has to offer and Anquetil used it in the identical way while leaning forward instead of backward as T o'W men do.
 
Apr 21, 2009
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Was waiting for your return and to be honest it's fairly underwhelming.

Go study anatomy and biomechanics before your pedal (ha ha get it) this bullschniz!

When I learned anatomy I discovered our lecturer's comic side as he asked me to sort through the box of knees to find an uninjured one, and then after an hour playing with a cadaver he took the group out for dinner at a steak restaurant.

So sorry Noel, the Google search you used to confirm your bias was wrong. Try again.
 
Jun 4, 2015
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Re:

CoachFergie said:
Was waiting for your return and to be honest it's fairly underwhelming.

Go study anatomy and biomechanics before your pedal (ha ha get it) this bullschniz!

When I learned anatomy I discovered our lecturer's comic side as he asked me to sort through the box of knees to find an uninjured one, and then after an hour playing with a cadaver he took the group out for dinner at a steak restaurant.

So sorry Noel, the Google search you used to confirm your bias was wrong. Try again.
A study of biomechanics and physiology may teach you what each muscle is capable of doing but not what a combination of the hip/leg's three most powerful muscles can do when given a particular task in cycling. If you don't know your objective is, no amount of these studies will lead you to the perfect pedalling technique. That's why ye still have a dead spot sector after over a century of studying pedalling biomechanics. My simple objective was to pedal in such a way that made it possible to combine max arm power with leg power when riding at speed in the saddle while in a racing aerodynamic position. This is impossible with the natural pedalling style because if you try it you will only pull yourself out of the saddle. You need to be applying a maximal forward force at TDC to do it. But then I was assisted by my use of the equivalent of! ' Scott Rake ' aero bars which I had been using even before B Lennon invented his aero bars. D Fosbury's simple objective was to keep his body's center of gravity as low as possible when going over the high jump bar.
 

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