2 Creativity With A Bicycle

It may be no understatement to tell someone that all that can be possibly tried out with bicycles have been already tried. I wonder how much is left to do? Maybe 2%? Okay. 3%. I suppose that the probability that your new bicycle idea is unique compared to what's come and gone is very small. I hold the theory that given something that is really popular among the masses, and a lot of time span in years, that probability gets even smaller.

Here are a few of those ideas from history. The creativity is compelling. More here for your weekend pleasure.

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4 Carbon Fiber Clear Coating And Repair Guide

FYI : A gentleman has written a nice guide to clear coat carbon fiber for your bike project. He titled it like so : "Comprehensive Guide To Clear Coat Techniques For Carbon Fiber". Apparently, all you would require is some 60-70 dollars worth of materials, free time during your weekends and lots of patience. The guide also goes over protecting a paint job that you may have and may also help you assess whether surface scratches on carbon fiber parts are worth worrying about. Want to get rid of them? There's a solution for that too - polishing using buffing and polishing compounds. I hope you will enjoy this and even try some of his tricks and methods.

Hope you're all keeping well and happy. Email me with any queries or interesting topics you come across.

Ciao.

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11 The Cyclists' Apocrypha

Originally published in Cycling Plus, 2001.


In the beginning God created the bicycle, saw that it was good, then went for a nice Sunday ride on the bike lanes He'd made the day before, and they were good too, because they were new and He had the angels keep them clear of debris. Later, of course, God would get cross and have the flood wash all the good ones away.

And God said to Himself, "Let us create man, because cycling is too much fun to keep to Myself," and so He created man, him did He create, create did He him do. And God put man in paradise, and commanded him, "Glideth upon the earth anywhere thou wisheth, except for that big hill over there. For on the day thou goeth down that hill, thou shalt surely die."

And God said, "Man needs a companion to keep him from spending too much money on new bicycles." So God caused man to fall into a deep sleep by asking him if he wanted to go clothes shopping at the mall, then took a rib from him. Then God said to Himself, "Who am I kidding, I'll never hear the end of it when she finds out she was just a rib," so He created woman from frankincense and myrrh and a certain je ne sais quoi.

And God said, "Let man have dominion over lathe drills and Philips head screwdrivers, and let woman have dominion over everything else, and as long as thou art naked and unashamed, thou might as well be fruitful and multiply."

Lastly, God created the chicken and the egg, in that order, which should clear up that matter.

Now the serpent, he was a wily one, and he said to woman, "Yea, hath God said you may cycle anywhere but down that hill?"

And the woman said unto the serpent, "That's about the size of it: go downhill and die." And the serpent said, "Ye shall not surely die, you probably won't even fall off. For God doth know that on the day you go downhill, you will not need to pedal for a long time. Go on, give it a try."

And the woman saw that the hill was good, she did not need to pedal for a long time. She told the man about it, and he also went downhill. Their eyes were opened, they saw they were naked, and they sewed fig leaves into padded cycling shorts because sometimes it got bumpy going downhill.

And they heard the voice of God as He was off-road, fully suspended of course, and they hid their bicycles at the bottom of the hill and started whistling nervously. And God called unto the man, and said, "Where art thou?"

And the man said, "We art down here."

And God said, "Hast thou cycled downhill, whereoff I commanded thee that thou shouldest not?" And man said, "C'mon, it was her idea."

And God said unto the woman, "I will greatly multiply thy sorrow whilst climbing hills; in pain shalt thou perch upon thy saddle."

And God said unto the man, "Because thou hast harkened unto the voice of thy wife, cursed is regular bike maintenance. The inner workings of the hub gear will be beyond thou to repair. In the sweat of thy face shalt thou service thy freewheel."

And God said, "Behold, the man doesn't listen very well," so he kicked him out of paradise and guarded the entrance with a sign of a picture of a bicycle in the middle of a red circle. And He had a Cherubim with a flaming sword stop by a few times a week for good measure.

This is the book of the generations. The first bicycle was a single speed, Godspeed, but after that it got complicated. Sprockets begat sprockets and cables begat kinks. Celerifere begat Draisienne begat Macmillan begat Michaux begat Ariel begat Bayliss Thomas begat Lawson begat Rover begat Boneshaker begat Ordinary begat Raleigh.

And it came to pass, when men began to multiply on the face of the earth in a critical mass, God saw that the wickedness of man was great and he did not like to give way to anyone on the road even his mother, so He directed Noah to build an ark made out of renewable resources. There went in two and two unto Noah into the ark every type of bicycle: one to ride and one for spare parts. And Noah gathered two touring bikes and two mountain bikes; two recumbents and two tandems; two road racing bikes and two cross bikes; also four unicycles, just in case there was a misunderstanding, and a brace of Bromptons, as their folded countenance pleasethed Him. And God said there might be Some strong winds in the Southeast. And it rained for 40 days and 40 nights, then drizzled for another fortnight.

And God remembered Noah and asswaged the waters, and Noah opened a door on the ark and set loose Japheth on a unicycle, and God said, "This is a covenant which I make between me and you and every living creature: that a man on a unicycle is a hilarious sight. The waters shall no more become a flood to destroy all flesh."

A bit later, God spake unto Moses, saying, Here are a few ground rules, I hath numbered them for thou for easy reference:

I. Thou shalt hold no other races above the Tour de France.
II. Thou shalt not make unto thee helmets which cost more than £100.
III. Thou shalt not take My name in vain everytime thou gettest a flat tyre.
IV. Remember to oil thy chain, to keep it rolling.
V. Honor the Zebra Crossing and those walking upon the face of it.
VI. Thou shalt not ignore other road users, nor cycle recklessly upon the pavement.
VII. Thou shalt not steal bicycles.
VIII.Thou shalt not kill, except bicycle thieves.
IX. Thou shalt not hang onto moving cars.
X. Thou shalt not covet they neighbor's new Cannondale, nor his group set, nor his £3000 MTB, nor even his stylish shades.

Forget not the Titanium Rule: Signal unto others as thou wouldst have others signal unto thou.

And moving right along, there came four horsemen of the Apocalypse, and they were the Taxicab Driver, and the Motorcycle Messenger, and the White Van Man, and the Man Opening a Car Door Without Looking.

Amen

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20 Bicycle Chain Wear Test From Wippermann

Wippermann is a German bicycle chain maker. Their stainless steel chain Connex 10sx tops a list of chains in their on-going wear test to 1% elongation (click on above). If you'd look, the wear life variation is huge between the top and bottom of the list. I also believe theirs is the only stainless chain in the list so you can go "hmm?" to that.

The testing is being performed on a rig with a 52-tooth front ring and a 17-tooth rear cog, with an applied chain tension of 300 N. The test phases feature the following phases :

- An in-line 5 hour run with original lubrication.
- A offset test to both left and right side for 5 min at 50 Hz and then 10 hours at 100 Hz after independent applications of water, oil and sand to the chain.
- An inline 15 hour test at 100 Hz with above mentioned pollutants, which is then repeated every 15 hours after cleaning until chains show a 1% change (or 8mm increase from DIN specified length of 800.10 mm). This change happens due to wear of pins against the roller.

The following video put together by Cantitoe Road shows the test protocol. A text description of the phases can be found here.



What I'm hoping they'd add into the bevy of substances to soil the chain is de-icing salt used commonly in wintry regions. Some salt water spray would be appropriate. The chains could then be stressed to twice its recommended working load and then inspected for cracks or changes in cross-section.

Salt could be one of the prime culprits in the recent case of Shimano 6700 chain failures. We were all left guessing in that post and some of us even declared it a materials issue. Well, the news is that of the affected parties sent in his chain for hardness testing to a third party facility and the tests didn't point to a materials related defect. Puzzling eh?

But the people who work in marine environments know the almost invisible, catastrophic failures on loaded chains, whether they are galvanized or stainless. Microscopic cracks develop and grow within and sooner or later, you may have yourself a broken product.

I was also hoping that multiple sprocket combination could be utilized in this test, as opposed to just one fixed combination of 52/17T. I have written recently about chordal action in tiny sprocket sizes, those lesser than 17 T.

In that post, I calculated the variation in chain speeds of a 52/11 and a 52/12 combination and wondered about the long term effects this would have on sprocket wear. Dan Connelly asked me whether I had any data with me to back this issue. At that time, I replied that I had none.

It would be interesting to see whether the theory agrees with practice.

CONNECTED READINGS :

52x11 vs 52x12 Gearing : A Look At Chordal Action
Wipperman Press Release (2008) : Wippermann Chains, Strongest In Industry

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4 Pedaling Force Signatures?

Metrigear has been testing their Vector power meter for sometime now and technicians are regularly posting test data on their blog. These folks are taking a physicists approach to giving you pedaling data by getting right down to the finer details, such as the direction of pedal force vectors. The sensors on this system are sealed inside the pedal spindle and the system collects data at a claimed half a million cycles per second.

A vector is something that signifies both magnitude and direction of a quantity. Only certain quantities can be vectors. Speed is not a vector, but velocity is. Why? Here's a tricky one. Is time a vector or scalar?

Below are images of leg force vectors from two cyclists (borrowed from the Metrigear blog). Both are standing on the pedals, with Cyclist A applying 460 watts of power to the pedals at 77 RPM and Cyclist B applying 550 watts at 91 RPM. Red vector lines belong to the left leg, while green belongs to the right leg.

Size of arrow signifies magnitude of force and the orientation gives direction. Source.

The recent blog post in which they uploaded all this information into was curiously titled "Is Your Pedal Force As Unique As Your Fingerprint?".

Some of you may think that it warrants looking at many different snapshots of leg force over a power spectrum. To me, the question is not a logical one. Comparing the nature of pedaling, which is highly variable, to genetically determined ridges on your skin is a little absurd.

Wouldn't you think that pedaling signatures for just one person alone could be different from day to day. Suppose one had a heavy breakfast, or wore a backpack or decided to shift a bit forward while biking, vectors could change pretty noticeably, wouldn't you agree?

For some, these sort of 'precision' measurements can take the life out of cycling and is an unnecessary luxury. For others, its a novel way to spend more money to enable them some more understanding of what they want to do.

I personally think average pedaling power and cadence is what is ultimately more relevant compared to instantaneous variations here and there in the pedaling 'clock' diagram. Unless one side is really off balance, which you would be able to tell without any instruments, I don't know how practical all these beans would be.

Anyone with a basic understanding of periodic waves will have a feel for the fact that to produce a constant power of so many watts, each individual leg will need to produce little over twice that amount. The average value of a pure half sine wave is 0.637 times the peak. Some deviation from the ideal "springy" waves is seen because of the variable output from human power, like in the image below.

Left and right pedaling force. Source.

The fact that each leg enters its power phase when the other is resting is one of the beautiful things of bicycle design. Perhaps this design was a natural step in its evolution after all that running Karl Drais did across the countryside with his 'hobby horse'. Bicycling in one way is an evolution of basic locomotive movements. Its value lies in the fact that, save for a few extreme terrain conditions, you can use gears, ball bearings and a pair of wheels to easily amplify this motion 10, 50, even 100 times.

Anyway, let's go back to Metrigear. Are you the type of person who thinks all this bean counting isn't really necessary? Or are you the one who always feels you're on the short side of data and you hunger for more, knowing you'll pay for it of course ?

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