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Pedaling systems(16 posts)

Pedaling systemsKristin
Nov 20, 2001 7:33 AM
What kinda funky pedaling schemes have been thought up over the years? The tried and failed stuff. Anything that had promise but failed for seemingly no good reason? Any websites out there that house info on past cycling innovations both good and bad??

Just curious...my cranks are turning around a couple of ideas and I'd like to see what's already been attempted.
re: Pedaling systemsAkirasho
Nov 20, 2001 1:42 PM
... well, there was Shimano's Bio Pace rings... and I've seen tons of variations on the theme... either with the rings, the crankarms or both.

There are Power cranks that force you to pedal more or less in circles... that is, unless you pull through, up and over, the crankarm will fall to BDC (if you could imagine having two crankarms at the bottom of the stroke).

There are variations on this where some type of cam mechanism is within either the crankarms or BB to "improve" power output.

There is some validity in at least looking for alternatives to traditional pedal modes... The human muscle groups related to pedal stroke are most efficient at different points through said pedal's stroke... so it makes some sense to try to maximize this... however, few can agree on how best to do this.

One problem is, a great idea is not enough... it has to be marketable to succeed (or at least garner wider use). Even if it is marketable... someone might own a patent and for whatever reason... decide to sit on it till it fades from memory.

One interesting take is the current standards for road wheel diameters... we accept the standard (650C and 700C), but wonder if a few mm larger or smaller might be worth it (Note, Gary Fisher is proposing 29" wheeled MTB's)???

I'm sure there are sites out there that document such... do a GOOGLE search.

We abide.

Remain In Light.
29" wheels and other stuffKerry Irons
Nov 20, 2001 5:39 PM
Actually, the "29 inch" standard proposed by Gary Fisher is what we roadies know as 700c, which used to be known as 28". The MTB folks just can't bring themselves to use the same wheel size as is used on the road.

It's not too likely that a new idea is possible in cranks, drive trains, and "pedaling" systems. There have been more mechanical patents on bicycles than for any other device. And if you watch carefully, you'll note that the innovation of merit all pretty much ocurred before 1920 or so. Refinements in execution, but no significant change in the basic concept, despite many attempts.
What? No significant change?Kristin
Nov 21, 2001 7:15 AM
What about clipless pedals? Stiff cycling shoes? Index shifting? Carbon fiber? Those seem like pretty significant innovations to me. Besides, my lifes motto is: "Anything can be improved upon." A good percentage of ideas proove impractical or one reason or another, but an idea is always worth exploring. If for no other reason than to keep ones mind sharp. And the bicycle can be improved upon!
Lots of changeKerry Irons
Nov 21, 2001 5:57 PM
I had the impression that your statement "pedaling systems" referred to things like oval chain rings, lever cranks, belt or shaft drive, automatic shifting, cam cranks, etc. Maybe you could tells more about what you mean so you would get less scatter in your replies.
I described my idea in a post below:Kristin
Nov 23, 2001 7:29 AM
This one: Kristin 11/21/01 7:43am
re: Pedaling systemsStarliner
Nov 20, 2001 7:30 PM
Twenty or thirty years back scientific research discovered the 'dead' area of the pedal stroke, resulting in a lot of silly products coming to market meant to address this issue.

Shimano's BioPace was one of them. Heavily marketed and hyped, it took over the market for this type of product at the time. Racers hated BP because they couldn't spin circles with it, only squares. It turned the proper adjustment of the front derailleur into a highly trained skill, and introduced many a cyclist to the phenomonon known as chainsuck.

Other notables include the Allenax transpedal system, which was actually an entire bike; and the Houdali (sp?) Power Cam crankset.

The Power Cam used a cam lobe on the inside of the crank spider arms, which interacted with a set of rollers on the BB. I'm not sure exactly how it worked. Though it was rather heavy, people who rode with them rode some pretty big gears. I think it came standard with a 62 tooth chainring, and I have heard that Olympic riders set some records with them. After being around for several years, they sort of died on the vine, maybe a victim of Shimano's marketing efforts with Biopace.

In the post-biopace period, I've heard of a product called Powerpedals which is supposed to help correct the pedal stroke, but somebody else is going to have to fill you in on that.
re: Pedaling systemsn crowley
Nov 21, 2001 2:11 AM
All research done on cycle racing (pedaling) both for
racing advantage and medical purposes was based on the
understanding that there is
only one infallible way to
pedal and that is the "round pedaling, scraping the mud off
your shoes" style of pedaling and so all ended in failure.
With the round pedaling style, there will always be a top
dead center for each pedal and riders with less than
perfect lower backs will always be subject to varying
intensities of lower back pain. The completely different
linear pedaling style that was used so sucessfully by
Jacques Anquetil, completely eliminates the upper dead area
and also all chronic lower back pain. It enables a rider to
apply continuous constant maximum chain drive power to the
chainwheel throughout it's entire 360 degrees circumference
and because it hinges all the necessary and unavoidable
strain in the hips instead of the lower back (as the round
pedaling style does), all chronic cycling related lower back
pain is eliminated. By using the knees in a way that is
similar to walking, it also reduces the risk of injury in
this area. Andrew Bradley has an excellent site on pedaling
" thankstomycranks cycling pages " and in it, he raises the
question, why does climbing have such an effect on the
normal racing cyclist's style of pedaling.
In my oppinion the answer lies in the " top dead center "
associated with the round pedaling style. If one is cycling
on level roads and stops pedaling, there is only a slight
gradual reduction in speed but when one tries this on a
climb, there will be a dramatic drop in speed, as if pulling
a brake on a level road. So when climbing and using the
round pedaling style, one stops applying effective power
to the chainwheel for two brief periods on each revolution
of the chainwheel and one is forced to compensate for this
negative power by applying extra pressure to the pedals for
the remaining two thirds of the chainwheel revolution.
When one uses Anquetil's pedaling style with uninterrupted
continuous power application it eliminates the above problem
and makes climbing much easier.
It is not new equipment that is needed but the commonsense
to realize that there may be a more efficient and safer
method of pedaling.
Very InterestingKristin
Nov 21, 2001 7:43 AM
Thanks for the info. Now my brain is beginning to twist in a whole new direction. One that my mechanical/mathmatical skills are not prepared to take me! I'm always tempted to keep my ideas secret and work on them in my mad-scientist labratory. But I'd like to hear your thoughts on this concept.

What if a change were made in the shoe itself and the metal shank were not straight, but rather curved to fit the riders natural arch? The sole of the shoe would fit perfectly against the foot (same idea as Birkenstocks). In this senario, the cleat would be placed a little further back--just behind the center of the ball of the foot. If my thinking is correct, the rider could focus more power through the downstroke. This would mean a custom fit shoe.
Very Interestingn crowley
Nov 21, 2001 8:09 AM
I have never used clipless pedals, they are not suitable for Anquetil's technique because when using his style of
pedaling, it is more forward leverage than direct downward
pressure that is used and for that reason you need to make
pedal, shoe and foot a non flexing unit. I did try all possible positions for best cleat position and I have to
agree that the experts are right, at least for pedals and
toe-clips with straps. I cannot speak for clipless pedals
and direct downward pedal pressure.
AnquetilJofa
Nov 21, 2001 9:40 AM
If you want to climb like Anquetil you'll have to throw yourself into your pharmeceutical experimentations, on top of already being small and light, and having a spectacularly efficient cardiovascular system. His magic ankles are red herrings.

Jofa
another exampleCCM
Nov 21, 2001 9:50 AM
of small light pharmaceutically enhanced with strange footwork- Pantani
Anquetiln crowley
Nov 22, 2001 3:58 AM
You also appear to fit into that group of brainwashed
(round pedaling style) experts and coaches who claim that
Anquetil was some sort of genetic miracle or that his extra
pedal power was drug related.
Competitive rowers combine arm and leg muscles for smooth
and powerful rowing strokes. By completely altering the
pedaling technique, Anquetil made it possible for a cyclist
to avail of all this additional upper body power and that explains his smooth powerful high geared pedaling style
that completely eliminates the top dead spot area.
As for resting the muscles in that area, there already is an excellent technique for resting leg muscles. All of
which goes to prove, some cyclists have a lot to learn.
"Brainwashed experts" (in what?)Jofa
Nov 22, 2001 1:37 PM
He probably wasn't a 'genetic miracle' (whatever that may be- I shudder to think), just a very fast cyclist in an era when the spread of top cyclists' performances was wide and unpredictable. Also he is thought to have been a keen experimenter with performance-enhancing drugs, which is no great slur as it was ordinary at that time, as it has been in ours.

That Anquetil was a great cyclist is in no doubt, but the allegation that he was privy to some secret pedalling style to which other riders were ignorant, and moreover that this 'style' recouped dramatic losses of energy which his 'foolish' competitors squandered at every pedal stroke, is hero-worship of the most tediously submissive degree. He had an eccentric gait on the bike, and he exhibited it in his walking too. Look around you: people have all sorts of different walks. Michael Johnson runs with a rod up his back but this isn't now being tought as the 'new efficient method', despite his domination of the middle sprints. It is correctly seen as a quirk, nothing more.

You're buying snake oil, by the gallon. How about this- for free: ride your bike; enjoy it; if you want to go faster- get fitter. That's how the pro's do it.

Jofa
"Brainwashed experts" (in what?)n crowley
Nov 23, 2001 1:14 AM
Brainwashed into believing that the round pedaling method of
pedaling is the only way to pedal. Riders are spending their
hard earned cash on over expensive equipment in order to save seconds in a tt, while countless riders throughout the
world are forced to suffer lower back pain or else give up
the sport. By using Anquetil's combined arm/leg power way
of pedaling, minutes could be saved and all cycling related
lower back pain eliminated, and all for free, if the experts
swallowed their pride and accepted the fact that they were wrong and there was a more efficient and safer way to
power the pedals. Saying Anquetil was genetically a freak
of nature with an enlarged heart etc was an easy escape for
the experts from having to admit that all his success was
due to his mysterious pedaling.
The proof of the effect that Anquetil's technique had on
the back can be found in the recently released video on
Anquetil's racing career, in the statement of his teams
masseur " When lying face down on the massage table, the
backs of all the riders were curved downwards but there was
no curve on Anquetil's back, it was flat and felt very
powerful". The difference was such that it left the masseur
still believing that Anquetil's mysterious power came from
his back. In reality that difference was due to the effect
of the years of continuous strain which round pedalling
puts on the back. Anquetil's technique puts all that strain
safely in the hips and strengthens the back.
Very InterestingJofa
Nov 21, 2001 9:38 AM
If you're looking to redesign a system such as this so as to make it more efficient, then first you need to find the existing inefficiency: where is your energy actually being lost; and in what form is it being lost.

One might look for evidence of energy ‘in' not making it ‘out', at least not out the place you want. This may be in the flexion of some component, but be careful: that component might just store the sneaked energy and release it back into the system later. If it actually ‘steals' the effort then it must do something with it, and in the real thermodynamic world, that means it converts the energy into heat, and the component warms up, and radiates the heat (your leg effort) away. Sadly for us (‘Efficiency Police'), however, the stuff bicycles are made of (springy metal) are very bad at this- they give virtually all of your energy back to you, and barely warm up at all.

Otherwise, one could look for some aspect of the design which limits the amount of energy ‘in' in the first place: a bottleneck, maybe. Could be promising: this is where the designers of Biopace, EggRings, Rotorbike et al applied their efforts.They reason that the problem isn't with losses in the system, but that the system's restraints don't allow the cyclist to apply his effort properly at all times. Ergo, the system could be redesigned in such a way that the rider can apply maximum effort at all times. The theories behind these principles are complex, especially when human legs are thrown into the equation, but Andrew at thankstomycranks.com goes into it in some detail. I don't think these ideas should be thrown out of the window quite so energetically as some people choose to, especially when with the other cheek they are lapping up all sorts of marketing nonsense about their ‘supple' frames, or whatever, but, I certainly doubt whether it's all worth the trouble.

I think the difficulty with the task you've set yourself, one which virtually every cyclist does at some point or another when they're spinning along daydreaming, lies with yourself: your body. You are extraordinarily adaptable, and operate equipment such as bicycles from the ends of long, low-friction-jointed levers (arms and legs). In those moments when you can't apply much effort, which your bike imposes on you, - like TDC- you aren't wasting energy: you're actively recuperating. If you had pressed hard on your pedals then, you'd have been a bit more tired for the downstroke; but you didn't, so you aren't.
Losses in this biomechanical system are extraordinarily hard to locate and quantify, much less do anything about. Maybe by luck or fortitude one of these new designs will manage to allow its rider to apply a bit more energy, one day, and even go on to be mechanically practicable. In the meantime, I find it's my leg muscles, my heart, and my impending nausea which contrive to restrict my attempts to cycle at 34mph, to about 24. Not my cranks or shoes.

Jofa