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Monday
Mar282016

Smaller Wheels

I was recently sent a picture of a Fuso track bike I built around 1990. It is different in that it has smaller 650C wheels. At the time this smaller tire size was becoming popular with triathletes with much talk of them being “Faster.”

People in the know, such as myself and Terry Shaw, owner of Shaw’s Lightweight Cycles in Santa Clara, just south of San Francisco, knew there could be little or no advantage. However, Terry Shaw thought that if there was an advantage, it might be in the initial jump during a sprint race on the track.

Smaller wheels have the effect of lowering the gear ratio, so this would have to be compensated with more teeth on the chainring, or less teeth on the rear sprocket. And so if you have two bikes with the same gear ratio, where is the advantage? Except that smaller wheels and tires have to be marginally lighter.

It interested us both enough that I agreed to build Terry Shaw a track bike that he would ride himself. The only way to test the theory was to actually race on it.

Building a bike with smaller wheels changes the whole design of the frame. The front fork is shorter, so the head tube is longer as you can see in the photo above of a 60 cm frame. It looks larger because one is used to judging frame size by the length of the head tube.

With the wheels being a smaller radius, the angle of the down tube and chainstays has to be altered to in effect raise the bottom bracket. Smaller wheels also means less trail, so to compensate the fork rake or offset was shortened to increase the trail. This was a scant 20 mm or roughly ¾ inch, and is also evident in the above photo.

For readers who don’t fully understand the concept of “Trail” and how it affects steering, here is a drawing.

Draw and imaginary line through the steering axis and it reaches the ground at a point in front of where the wheel actually contacts the ground. The wheel therefore pivots about that point of contact.

This provides a castor action and the wheel trails along behind the steering axis, Hence “Trail.”

Looking at the drawing you should be able to see why smaller diameter wheels makes for less trail.

A steeper head or steering angle also makes for less trail. More rake or offset means less trail, less rake, more trail. Which is why this frame had a far sorter fork offset.

The drawing is for a road bike, the trail makes for a bike that will hold a straight line, and also gives some self-steering characteristics when cornering. A track bike typically has less trail, because it is designed to be ridden on a banked velodrome, where the banking has the effect of riding in a straight line.

The rider needs a quick handling bike, one that the rider can physically steer and change direction easily. It calls for a bike with a steeper head angle and less trail than a road bike.  

So now I have explained what went into the design of the frame, how did it perform? Terry Shaw raced it for a whole season, but then went back to his conventional track bike with 700C or 27 inch wheels. He reported the bike was faster in the initial jump, but was harder and required more effort to keep it rolling once top speed was attained. So no real advantage.

The one pictured above may or may not be Terry’s actual bike, because I built one other for a customer of Shaw’s Cycles. Soon after this I did design and built a TimeTrial/Triathlon bike for a trade show. I can’t show you a picture because it was later sold to a bike store in Del Mar near San Diego, and I never saw it again. I have no idea where it is now and would love to know.

It was an interesting design concept. It had a 650C front wheel with a fork with even less rake than the track bike above, it also had a steeper head angle. With the rear wheel there was the option to use either a 700C or 650C wheel. There was an aluminum adapter plate that bolted on to special braze-ons on the seatstays to accommodate the different brake heights.

When the larger rear wheel was used it of course raised the rear end making the frame angles steeper, including the head angle. This changed the trail and the handling characteristics. To compensate the front fork brake mount was made so the fork could be turned and the fork blade was curved backwards like a motor-pace or stayer bike.

This increased the trail to compensate for the loss of trail due to the steeper head angle. The head angle and the fork blade offset was designed for optimum handling in either set up. In test runs it handled beautifully, but I only ever built the one.

My thinking was to use the larger wheel for flat and straight courses, and the smaller rear wheel for technical courses with a lot of twists and turns, where faster acceleration out of corners might help.

 

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Monday
Mar212016

Fine Italian Steel

On hearing the term “Fine Italian Steel,” one usually thinks of handcrafted steel frames, but in the early 1950s, Italy having made a quick recovery from the devastation of WWII, were producing some quite beautiful steel bicycle components.

There were no Campagnolo Groupos in the early 1950s, Campagnolo made quick release hubs and derailleur gears, and that was it. Pedals and cranksets were introduced in the late 50s.

The two main brands I remember were Gnutti and Magistroni, between them they made cranksets, bottom bracket bearings, hubs and headsets.

Gnutti made a really elegant cotterless crankset, (Pictured above.) that fitted onto a tapered and splined BB spindle, and was held in place with recessed Alen screws.

They also made a less expensive cottered crank, which was the one I used, pictured left.

Both Gnutti and Magistroni cranks were a three arm pattern with the same standard bolt circle diameter.

They were often used in conjunction with the French made Simplex chainrings.

Simplex had these three simple bolt-on adapter arms. (Picture below.)

 Gnutti’s quick release hubs were a copy of Tulio Campagnolo’s original idea, I’m not sure if the patent had run out, or they were made under license. The hubs had a chromed steel barrel with aluminum flanges pressed and swaged into place. (Pictures below.)

 Finally this Magistroni headset (Pictured below right.) intrigues me, it is quite an engineering masterpiece. How did they get the “Magistroni” name around its circumference?

It would not have been cast, a casting would not work as a bearing surface.

Stamping not possible around the complete circle. It would not have been engraved or pantographed, too costly.

Knowing a little about engineering practices of that era, I believe the lettering was rolled on.

Probably done while the bar stock was in a solid piece, before the headset cup was shaped in a lathe. The bar would be turned slowly and a rotating die with the lettering in reverse pressed into it under great pressure. If anyone else has any alternative theories let me know.

Also note the teeth machined into the top of the bearing cup, with a lock ring with matching teeth. After loosening the top nut, this would allow adjustment by hand, one notch at a time. The lock ring being keyed to the steering tube would prevent the bearing cup from turning as the top nut was re-tightened.

 

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Monday
Mar142016

Passion

Cycling is a passion, or rather, it can become one. Many people ride a bike, not all of them can be described as passionate about it. Passion is one of those words that is not easy to explain, one has to experience passion to know what it truly is.

Cycling becomes a passion when someone rides a bike for no other reason than to experience the joy of riding a bike. If you have a passion for something in life, you are truly living. Without passion, a person is simply existing.

People who say, “Cyclists should not be on the road because it is dangerous,” just don’t get it. It is like telling a surfer it is dangerous to go into the ocean because of shark attacks, the surfer who is passionate about surfing is not going to stop.

It is not that cyclists and surfers are crazy, foolhardy, with little regard for their life. In fact, the opposite is true. If one has a passion for life, the last thing that person wants is to end it. On the other hand, if one cannot engage in their passion, they are no longer living anyway. Life becomes a pointless existence. 

Passion can include anger, especially if someone suggests I should not pursue my passion, which happens to be riding my bike on the road. It is a road bike after all, and just as a surfer must surf in the ocean, a road bike must be ridden on the road. 

Some will say, “You have a local bike path, why don’t you ride there?” Yes I am fortunate to have a paved Walk and Bike Trail just two miles from my home. It is 7 miles long, so 14 miles out and home. But after riding it several times during the week, the monotony has got me itching to get out on the open road, and actually go somewhere.

On weekends I pick quiet country roads to ride where there is very little motorized traffic, and actually I prefer to deal with a few cars and trucks over the dog walkers and runners on the shared path.

Of course, they have a right to be there too, so I am not complaining. Some of them may be are following their own passion. 

 

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Monday
Mar072016

Siblings

I sometimes look on the bikes I built as my children, and like any parent it does my heart good to see them doing well, like the one pictured above.

Still owned by the original owner since 1985. He recently sent this picture with the comment, “Apart from two small nicks in the paint, the bike still looks the same as the day I picked it up from the bike store.”

The Fuso was a limited production frame, still very much hand built and brazed by me, but unlike building custom frames one at a time, these were built in batches of five frames all the same size.

This was more efficient because not only were the frames all assembled on the same jig setting, but as I first brazed the Bottom Brackets, by the time I finished number five, number one had cooled and I could move on to the next step which was brazing the head lugs.

Then on reaching number 5 again, number 1 was ready to have the seat lug brazed. By rechecking alignment after each brazing step, there was very little movement in the final step of the brazing process.

The whole frame was assembled in this fashion, 1,2,3,4,5, and move to the next stage and repeat. When the frames were finished, they were stamped with a serial number in sequence.

Today it is interesting to see these batches of five same size frames slowly being added on my Registry. Occasionally, the more popular sizes were built in batches of up to 10 frames, depending on the demand.  I tried to keep all sizes in stock ready to be painted to order.

Like siblings these frames went their separate ways, now like a family reunion they are reconnecting on the registry. The red and grey Fuso at the top is #522, and lives in Dallas, Texas. Here is #523 painted two tone blue and lives in Las Angeles. #525 (I don’t have a picture.) lives in Boulder, Colorado. All are 56 centimeter, and interestingly are all three owned by the original owners.

Bikes in some ways are like people, some age well, others don’t. People do well if they eat right and exercise, and look after themselves in general. It also helps to have good genes, to come from good stock. Bikes too, where they came from and what they are made of plays a big role in their ability to stay “Young Looking.”

I have mentioned before the red paint I used was a Candy Apple Red, over a bright orange base coat. The reason this red looks so rich and deep is because what you are seeing is the almost fluorescent orange shining through the translucent red.

In bright sunlight this is even more evident. When I went to trade shows, (Which was how I built a dealer network, in pre-Internet times.) I went with a simple ‘Home-made’ display made of peg-board and painted white, and used florescent ‘Daylight’ lighting. The chrome and componentry sparkled like jewelry, and the paint colors, especially the candy apple colors, and pearlescent finishes just popped.

The best red pigments are made from cadmium, but due to the expense and the toxicity of cadmium, red pigments in paint, printer's ink or any other medium, are now-a-days synthetic and usually have a tendency to fade over time. Especially when exposed to a lot of sunlight.

I remember driving behind a car with a faded bumper sticker that read ‘OBER RIVERS.’ I was thinking, ‘What a great name for a rock band.’ Then knowing what I do about the pigment in the color red, I quickly figured out the this sticker had originally read SOBER DRIVERS, and the “S” and the “D” had been printed in red and had faded to the extent that it had completely disappeared. Leaving behind the rest of the message that was printed in black.

My point is that the Candy-Apple red method I used was not prone to fade over time. This is evident in the top picture of a frame that is over 30 years old and exposed to bright sunlight almost daily. The durability of the paint also speaks volumes for DuPont Imron, but another reason is that I “Cured” my paint by baking in an oven to a temperature of 250 degrees. The paint was ‘Hard’ from day-one, rather than waiting to cure naturally over a long period.

The other thing helping the durability of the paint job is the primer I used. It was an “Etch” primer, that contained phosphoric acid, which is also a rust inhibitor and being a mild acid, it etched itself into the metal of the frame, providing a key for the finish paint coats that would follow.

It gave me great satisfaction to build these frames, and it gives me even more satisfaction today to see them still being ridden, rather than being hung on a wall to be looked at. It is the gift that keeps on giving.

Addendum 3/16/16

Here is Fuso #525 mentioned in the above article.

 

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Monday
Feb292016

Art and Function

I love when a comment on one of my blog posts gives me food for thought, and better yet subject matter for another article. Steve wrote such a comment on my last tribute to Brian Baylis. He stated:

A bicycle, isn’t a piece of art, but something you ride. Because really, no frame builder builds all the components hung on his frame: wheels, tires, saddles, cables, brakes, derailleurs et al.

It is, in the end, a simple device envisioned hundreds of years ago as a means of moving men (yes, it was envisioned by men for men). So really, how much time should one spend building a frame, when all its components are produced by someone else?

(See the complete comment on my previous post.) 

So is a bicycle art or just something you ride? Well, yes and no. There is pure art, objects that serve no practical purpose other than to be pleasing to the eye. To live a life without art would be a pretty bland existence.

I am not a material person by any means. I do not place much importance on stuff, but I do have pictures on my walls, and a few pieces of handmade pottery around. They bring me pleasure, and my life and my home would be missing something if they weren’t there. That is the only purpose of these art objects.

Everything ‘man-made’ whether handmade or mass produced, is either pure art, completely practical, or mostly what I call ‘Functional Art.”

Because given a choice between two objects of equal performance and price, one will choose the one more pleasing to look at.

Furniture is a good example of functional art. A chair has to be comfortable to sit in, but also needs to be pleasing to look at, because it becomes part of the décor of our homes, along with the pictures on the wall.

There are degrees of function and art in functional art, and when one takes over from the other the product often suffers one way or another. But it all comes down to what the consumer or owner of the object wants, and what he can afford or is willing to pay.

When a chair becomes a piece of pure art, it may be uncomfortable to sit in, or too fragile for everyday use, and one might ask, what use is it.

If it brings pleasure to its owner just to look at it, that is its purpose. I would not criticize anyone for owning such a chair, or the person who made it.

So is a bicycle frame any different? I got into building frames to build a better bicycle. One that rode better, handled better, and was more comfortable. My customers in the UK were almost 100% racing cyclists. The bike was needed to compete in bike races, it sold because it was functional and the price was right.

When I came to the US I had to up the ante on my finish work because that is what the American consumer demanded. The bikes did not lose any of the ride or handling qualities, but I did reach a point where people began to say, “This is too beautiful to race, I will be afraid to crash it.”

This annoyed the hell out of me. I had been forced to move towards pure art in order to stay competitive, then the bike was no longer practical as a racing bike, because it was too fine and too expensive.

That is why I moved away from the pure custom frame to the limited production model like the Fuso. A Fuso will handle exactly the same as one of my super expensive customs, but the price was reasonable, and the degree of finish was acceptable to the people who wanted a piece of art.

On Steve’s point that the framebuilder only makes the frame, not the complete bike. It has always been that way. Even today, companies like Trek and Cannondale, design and produce a frame only, then assemble it with the same components as everyone else. And the bicycle always takes on the name of the frame builder or manufacturer. It becomes a Trek bicycle, or a Dave Moulton, a Fuso or a Brian Baylis bicycle.

Even lower end bicycles are built this way. The only exception I know to this was Raleigh Industries, in Nottingham, England. They had a huge factory that made everything. They had different thread standards, and even different rim and tire sizes, so if you bought a Raleigh bike, you were forced to buy spare parts and even tires from Raleigh. They went out of business some years ago, and I don’t know of anyone manufacturing the whole bike anymore.

To sum up, I believe there is room for art and room for function, and when you can successfully combine the two you have the best of both worlds. I never spent as much time building a bicycle frame as Brian Baylis, but I did spend a year and a half writing a novel. Was that a waste of time? You tell me, because I often wonder about that myself.

 

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