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Wednesday
Oct172007

I have nothing today

Because I was fortunate
To build a bike or two
Doesn’t mean that what I say
Is absolutely true

I try to write about the things
I've learned throughout the years
And stimulate the gray stuff
That's in between your ears

Sometimes I will write a piece
On this, that, or the other
Some of you will share my view
And then there’ll be another

Who express a different opine
With words that are quite strong
But often there’s no black or white
There is no right or wrong

And if I make you think about
Your safety when you ride
Then does it really matter
Our opinions collide

Better our opinions
Than your head on solid metal
And you are a statistic
When the dust has settled

I'm not some safety guru
With advice bike riders seek
I’m just the Devil’s Advocate
On a muddy two-way street

If my simple inane writings
Touch one reckless soul
Make him think about his safety
Then I’ve reached my goal

May the rest of you be entertained
And even crack a smile
So I know my time’s not wasted
It all has been worthwhile

Just get out and ride your bike
Be safe along the way
Live to ride, but ride to live
And enjoy another day

So may you be protected
By St. Christopher or God
And if you don’t believe in that
At least you’ve read my blog


Prompted by my last post and the reader’s comments. Seriously, I’d like to thank all for their intelligent, and thought provoking comments. Please keep reading even when I have nothing.
Dave.


Monday
Oct152007

Cyclists and POBs


I have been a cyclist since my early teens; most regular readers of this blog are also cyclists.

I don’t know about you, but I get tired of my reputation being tarnished by another group who should not even be categorized as cyclists.

Owning a set of golf clubs does not qualify someone to call themselves a golfer. A person might own a musical instrument, but they are not a musician unless they can play it. Yet anyone who throws their leg over a bicycle is immediately labeled a cyclist.

“As easy as riding a bike, anyone can do it,” is a common expression. Riding a bike in today’s heavy traffic is anything but easy; it requires considerable skill and a lot of moxie.

As a cyclists I am always lumped together with what I call POBs; (People on Bikes.) there is a big difference. I read in the paper of a “cyclist” killed in a traffic accident; I am left to wonder, is this really a cyclist or a POB? (Person on a Bike.)

They could be called "Pedestrians on a Bike," which is a contradiction in terms, but POBs behave like pedestrians. Most pedestrians don't follow too many rules; they wander around willy-nilly all over the place.

Some places have jaywalking laws, but apart from that, there are not too many rules enforced on a pedestrian. They will be on the sidewalk on one side of the road, when suddenly they will see a gap in traffic and without warning or signal will dart across the road to the opposite sidewalk.

As for traffic lights, most pedestrians don't even look to see if they are red or green, but rather look to see if there are any cars coming, and will cross with complete indifference to the color of the light. Sometimes they will not even look, because cars tend to give way to a pedestrian.

The result is, when a person gets on a bike they behave like a pedestrian; they ride on the sidewalk, they ride on the wrong side of the road against the flow traffic, and they ignore traffic signs and signals. At night they don't use lights, because after all, most pedestrians don't carry flash lights after dark.

Cyclists see themselves as a vehicle on the road, whereas, POBs see themselves as a person just trying to get from point A to point B and it’s too far to walk. They are often focused only on their destination, oblivious to everything else around them.

Sadly, statistics show that when a bicycle rider is killed on the road, it is often the victim’s fault. Running red lights, riding against traffic, or suddenly entering a road without warning in front of an oncoming car. This gives a false impression that cycling is dangerous. It is POBs that are getting killed, not cyclists.

A cyclist and a POB may look the same; what they wear or the type of bike they ride does not necessarily distinguish the difference. Some POBs even think they are cyclists.

These are a splinter group known as APOBs. The “A” is for Anarchist, Arrogant, or Asshole, pick any one. They grew up as POBs, later bought expensive bikes and started hanging out and riding with cyclists. However, they never became true cyclists because they disregard the laws of the road, at all times.

Worse, they somehow see themselves as above the law; they give all cyclists a bad reputation. Being ignorant of the law is one thing, but knowing better and still disregarding the rules and laws of our society is anarchy plain and simple.

If you know someone who is an APOB; then maybe you need to get together with a few other cyclists and hold an intervention. Tell them they can’t be a cyclist part of the time, and POB the rest; they have to pick a side.

The strange thing is many POBs drive cars, and when they do for the most part they follow the rules of the road. This furthers my belief that POBs see themselves as pedestrians on wheels, and think the rules on the road don’t apply. As “Motorists,” they suffer the same fate as cyclists; lumped together with PICs. (People in Cars.)

Motorists get in their cars and do nothing else but drive. Their full attention is on the road; they are the good and careful drivers. I see motorists as being the same as cyclists; they are just using a different form of transport.

PICs, on the other hand, drive as if they are still at home or at work. They talk on the phone, eat, drink, shave, and put on makeup. Another way to describe it; POBs ride their bike as if they are walking, and PICs drive their car as if they are sleepwalking.

Organizations who put out accident statistics should adopt the term POBs and PICs, in addition to the terms cyclist and motorist. We would then see that cyclists and motorists sharing the road is not the problem. It’s those SOBs the POBs and PICs.

Thursday
Oct112007

Same crap, different country

When a blogger from New Zealand linked to this blog the other day, I checked to see what it was all about. It turned out to be one of those articles about how dangerous cycling is, how cyclists make up their own rules and blow through traffic lights, etc, etc.

The piece started out in this fashion:

“Thanks to Al Gore, biking to work has attained a new cachet. You can exercise, get to work, and save the earth all at the same time.

But cycling is - particularly on New Zealand roads - dangerous. About a dozen cyclists die on our roads each year, and lots more suffer injuries as a result of accidents. And most commuters will be able to recount a near miss or two observed in rush hour traffic.”


Now wait a minute, let's back up here. A dozen cyclists killed a year in New Zealand. That's hardly a statistic to back up a claim that cycling is dangerous. I did some checking and discovered that New Zealand has a population of over four million people.

Twelve out of four million killed on a bicycle in a year must rank up there with people slipping in their bathtub listed as a cause of death. How many people died in cars in New Zealand in a similar period? A lot more than twelve, I guarantee.

In another part of the piece, there is this strange statement:

“Some cyclists seem to operate to an odd code which permits traveling through red lights and transferring occasionally to footpaths when it suits. Not to mention the odd sight of Lycra-clad cyclists in cafés sipping lattés.”

He said, “Not to mention Lycra-clad cyclists,” but he did anyway. This says a lot about the author of this article. The statement has nothing to do with safety or any other issue in the piece, but clearly shows he is anti-cyclist. I find a statement like this disturbing, coming from an educated man, who happens to be a lawyer no less.

I will go even further and say he is a bigot. If you were to substitute the words "Lycra-clad cyclist" with the name of a race of people or their color, this would be a bigoted statement. He is judging a whole group of people solely on their appearance.

I have explained before why I wear Lycra. For safety; bright colors can be seen; and for comfort; riding fifty miles or more in anything else is uncomfortable.

If I decide to stop for refreshment at the end of my ride with a few like-minded friends, am I to carry a change of clothes for fear I might be discriminated against? And what is the reason for this discrimination that seems to be world wide?

It goes beyond simple road rage. Is it because society as we know it can no longer discriminate against anyone on the grounds of race, sexual orientation, or religion? The "Lycra-clad cyclist" fills a void. Why this human need to make outcasts of anyone who appears a little different?

You can read the rest of the article here.

Tuesday
Oct092007

Is it time to re-think the derailleur?



One area of the bicycle that seems to be overlooked when it comes to equipment performance is friction; especially in chain drives and derailleur gears.

From an engineering standpoint the derailleur gear is an inefficient system. However, since its invention in France in the 1920s, no one has come up with anything better.

The system of a chain drive running out of alignment on multiple sprockets is not used on any other application except a bicycle as far as I know.

When the chain is not pulling in a straight line, there is extra fiction on the side plates and the bearing pins of the chain. There is also friction on the sides of the teeth on the chainwheel and rear sprocket.

When a chain is in alignment there is only slight friction on the bearing pins as the chain goes around the top portion of the rear sprocket and chainwheel. There is little or no friction on the side plates of the chain.

One thing a person notices the first time they ride a single speed fixed gear bike, is the smoothness of the transmission and the lack of friction. This is because the chain is in alignment, and there are no pulleys the chain has to run around.

The pulleys on the rear derailleur are the other source of friction; there is the friction of the pulleys themselves, and the chain has to go around a constant "S" curve. Turning the links of the chain, first in one direction, the other.

One derailleur popular in the 1930s and 1940s was the Osgear. (Left.) It had chain tensioning arm with a single pulley just under and slightly behind the chainwheel.

This meant the chain ran in the same direction and was not made to go around an "S" curve; there was also one pulley instead of two. At that time freewheels only came in 3 and 4 speed.

The Osgear had its shortcomings; it would not work with a double chainwheel because the tension arm was fixed. However, had it pivoted on a simple ball joint and had sideways movement, it would have aligned itself as the chain switched from one ring to the next.

The other drawback was, the fork that shifted the chain on the rear sprockets was over simplistic and shifting was not that good. Had it been designed like a modern front derailleur it probably would have worked much better.

A modern front derailleur is very efficient in that it will shift the chain over a ten teeth span or more, and once it has shifted the chain it is no longer in contact with the shifter and so causes no friction.

The Osgear had fell out of favor by the 1950s when the French made Simplex and Huret derailleurs appeared; they shifted better, and worked with 5 speed freewheels and double chainwheels. The Simplex and Huret rear derailleur had the chain wrapped around two pulleys in the "S" fashion; the way all modern rear derailleurs are designed today. I do feel the Osgear was a very efficient design that was never fully developed.

Campagnolo’s Cambio Corsa derailleur (Below.) patented in the 1930s but developed in the 1940 was a masterpiece of engineering for its time, but extremely difficult to use. A long lever released the quick-release, the wheel moved forward on a rack built into the frame’s rear dropout thereby loosening the chain. Another lever shifted gear while back-pedaling. At the same time, the wheel moved back tightening the chain, and the quick-release was re-tightened. There were no pulleys to tension the chain, so no friction.


Was the Cambio Corsa developed to its full potential? Has anyone ever experimented with sprockets that slide sideways on the rear hub so the chain is always in alignment? It would not be necessary for the hub to be wider, or the rear wheel dished more; the hub could be large enough for the sprockets to slide inside. Another idea, fixed rear sprockets, and a chainwheel that freewheels, gears could be shifted while coasting.

If the chain is to remain out of alignment, how about a chain with spherical rollers at each joint so it will run out of alignment without the friction of the side plates. I know all these ideas will cost more, but with the price of the top of the line bike what it is today, what is a couple of hundred dollars more for a drive train with less friction that will allow a rider to go faster.

The derailleur gear has remained basically the same for over fifty years; all improvements have been in shifting and the number of gears. Friction is overlooked because you can’t see it; and if everyone is using the same design equipment it is not an issue.

In some of my recent posts I have waxed nostalgic and longed for simpler times. I am not against change if it benefits the bicycle and the cyclist. Many changes I see benefit the manufacturer, and then sold to the consumer after the fact.

I am just throwing out a few off the wall ideas that may or may not be practical, but would it hurt one of the manufacturers to put a little money into some research and development to find out just how much of the rider’s energy is wasted overcoming friction?

Friday
Oct052007

Lugs

A bike store owner told me recently told me of a young customer in his store looking at a 1980s vintage steel bike that was in for a service. He pointed to the lugs and asked the store owner, “What are these for?”

I find it amazing that a method of building bicycles can be around for over a 100 years, and become lost to a new generation in ten years or so.

Since the bicycle’s invention in the late 1800s the traditional way to join steel tubes to make a bicycle frame was by melting brass into a lugged joint. Similar in a way to a plumber joining copper pipe by sliding the pipe into a pipefitting, heating, and filling the joint with solder.

Brazing, as it is known, done at a higher temperature and the resulting joint is much stronger. Early lugs were in fact pipefittings; these were heavy steel sand castings, cut square at the edges, and machined on the inside to fit the tube.

As steel tubing for bicycles became thinner and lighter, it was found the tube would sometimes break at the edge of the lug. This was because the lug was far stronger than the tube.

In any structure, if you make a joint far stronger than the parent material, the material will fail during stress, immediately adjacent to the joint. Framebuilders started filing the lugs thinner to bring the strength closer to that of the tube. For the same reason, they also started cutting the lugs into fancy shapes to eliminate the square edge of the lug.


By the 1950s the cutting and filing of lugs became the way a framebuilder would express his art and individuality. Hetchins (Left.) were one of the first to take this art to extremes.

By the 1960s and 1970s, fancy lugwork became too costly and lugs stamped from sheet steel and welded, became available. The top picture is a set of pressed steel lugs that I prepared during the 1970s, with some custom shaping a cutout work.

By the 1980s “Investment” cast lugs became available. A method developed for the aircraft industry, investment casting was achieved by first hand making a lug. From this “pattern” lug a simple plaster mould was made.

A lug made of wax was cast in the plaster mold; this in turn was coated in a ceramic material and fired in an oven. The firing hardened the ceramic coating and at the same time melted the wax from inside, leaving a void the perfect shape of a lug.

Molten steel was poured into the mold, and when cooled the ceramic mold had to be broken to remove the finished lug, hence the name, “Investment” casting. An expensive process, but the finished lug was near perfect, the tubes fit with no machining required; very little filing required from the framebuilder. Lugs, bottom bracket shells, and fork crowns are made this way.

Traditionally frames were never welded. Not because welding was not strong enough but rather the heat required to weld weakened the parent material adjacent to the weld. By the 1980s welding technology had advanced to where it could have been used to build lightweight frames. However, at the time customers, connoisseurs of the lugged frame would not accept it.

This changed during the “death” of the road bike in the early 1990s. Mountain bike manufactures could get away with the quicker and cheaper welding process, because the MTB was new and there were not the old standards, and traditions to break down. There was a whole new generation who grew up with welded BMX bikes.

When the road bike was reborn, sadly, for some of us it was an ugly bastard. Its gene pool contaminated by MTB and BMX, the beauty, style and class bred out of it. A well, that is I suppose the price we pay for progress.