Motor Pace Bicycle Racing

I am often asked the question:

“Why does bike designed for Motor Pace Racing have the fork turneded backwards. Is it to increase trail?”

The Stayer bike as it is called, has a smaller front wheel, a steeper head angle, and reverse fork; all designed to get the rider closer to the motorcycle that is pacing him. There is a roller mounted behind the pace machine, set at a regulation distance. It is up to the rider to get as close to that roller as he can for maximum drafting effect.

If you look at the drawing on the left, you can visualize that a smaller wheel means less trail, a steeper head angle also means less trail, but the reverse fork increases trail to compensate. A stayer bike may have a little more trail than the average track bike, but not an excessive amount.

Another reason to have the fork reversed is that occasionally the rider will bump the roller on the back of the motorcycle. If he does the roller will spin and the fork will flex easier in the direction it is raked or bent, thus absorbing these slight bumps.

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Thigh Length and Seat Angles

I am often asked if a rider with a long thigh measurement needs a shallower seat angle. The above line drawing represents two riders with the same inside leg measurement. As a result, they have their saddle set at the same height, and they are using the same size frame.

If the inside leg measurement is the same and one has a longer thigh measurement from his hip to his knee, it follows his lower leg from his knee to his heel is shorter. Conversely, short thigh, longer lower leg. As you can see from the sketch the position of the knee varies only slightly.

The exact knee over pedal (KOP) is not a precise measurement anyway as one is pedaling in circles, and it makes little difference if the rider sits back and pushes forward or is more over the pedals pushing straight down.

For the purpose of this drawing, I made the thigh length of the blue leg the same as the lower leg of the one represented by the red line, and vise-versa. The above line drawing could represent an unlimited number of riders with the same inside leg, with the red and blue lines being the extremes. If the inside leg measurement is a constant, it follows that as the one measurement increases the other decreases.

This simple drawing does not consider the length of foot. {Shoe size.) As the toe points down at the bottom of the pedal stroke, the foot becomes an extension of the leg. This of course affects saddle height and frame size but does not change the position of the knee by any large amount.

So, the answer is no. Once you have the correct size frame the seat angle should be right for that size frame. Then if your saddle is positioned at the correct height, the length of your thigh has little bearing on anything.

Also, as a footnote, some people agonize over the fore and aft position of their saddle. If you view that too considering what I have said here, it is less important. More important is the position of the handlebars in relation to the saddle. See the links below for more info on that.

You can read more about my frame design philosophy here:

And another article on Riding Position Simplified:

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Talking Bikes back in 1977

I was reading over an old article I wrote for the British “Cycling” magazine in November 1977, it really made me think. First thought was just how long ago that really was? 43 years and I was 41 years old at the time I wrote it, over half a lifetime ago for me.

I was reading this again in its entirety after several years, and the thing that struck me most was my choice of words, it was almost like I was writing this for children, it is not the way I would write today. However, I do not remember feeling that I was talking down to my readers as I was writing it. I think the reason was I was putting forward some new thinking and had the explain my reasoning behind every statement.

Everything I had read, and therefore everything everyone else had read before was stated as fact with no explanation as to why it was so. For example, there was a cycling handbook put out in the 1960s by the Italian Cycling Federation, it was advertised as being “The Bible of Cycling.”

It contained a section on frame design, which was really the “Gospel according to Cino Cinelli,” it stated that road bikes should always have a seat angle two degrees shallower than the head angle. This explained why Italian frames of the 1970s were 75 head, 73 seat, but gave no explanation what-so-ever why this was so.

I knew the reason because I had learned frame building from “Pop” Hodge in Luton, England, in 1957 when the standard frame angles were 73-degree head angle, 71-degree seat. The reason being, with the seat tube leaning back by 2 degrees, as a frame got bigger the top tube became longer. It made it easier to build a range of different size frames with the same standard lug angles.

A 71-degree seat angle was totally unsuitable for someone of my short stature which started me on this quest to build a better frame for myself. It just never made sense to me that someone with shorter legs, and a shorter body should have the same seat angle as a much taller person.

I remember one indication that I was questioning the Status Quo at the time in that an old gentleman wrote me a hand-written letter sent through the mail. He said that my ideas on head angles and “Trail” were all wrong and he enclosed a photocopy of an article from “Cycling” magazine dated 1946 to prove it. Back in 1946 and before that, it was thought that trail was a bad thing that made the steering sluggish.

One thing I said in this piece I need to draw your attention to is where I say “Frame size equals two-thirds of the inside leg measurement. This is somewhat simplifying the issue and two-thirds will not work for people with a long body and short legs. Overall height is a better indicator of frames size.

Click here to open or download the original article in PDF format. There are four pages standard 8.5 x 11 that can be printed or read on screen where you can enlarge the image for easier reading.

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The day the bicycle lost its heart and soul

When some one sent me a picture of a Fuso bike, (Above.) I knew at first glance that I did not build it. This one was built by Russ Denny, my former apprentice who took over my business when I retired in 1993. The frame had a sloping top tube, and while this is normal today, back prior to 1993 it was not.

I never built any frame with anything but a level top tube, with the exception of a few drop top ladies model, and the occasional twin tube “Mixtie” frame, which is a whole different frame design. I m talking of the standard road frame.

It made me think, what a run this simple design had. From the early 1900s until the mid to late 1990s, almost made it a hundred years without any major changes. Apart from basic geometry, tube angles, etc., once the standards were established, they remained the same, a level top tube was one of them, and any deviation from that was not acceptable, to either the framebuilder or the customer.

What I find amazing is that everything else changed so dramatically over the same period, I think of automobiles, aircraft, and just about any other manufactured item. They have all been though many changes over the same period.

It all started with the invention of the chain drive. The first was the British model “Rover” Safety Bicycle.So-called because its fore-runner was the Ordinary or High-wheeler model, (Below right,)

Although this was the first “Enthusiasts” bike, one had to be young, athletic, and have nerves of steel to even mount such a machine.

The Rover design pretty much established that the chain would drive the rear wheel, while the front wheel would provide a means of steering. The chainwheel, cranks and pedals would be just ahead of the rear wheel, and below the rider’s saddle.

The rider’s position was copied from the ordinary, and lead to those early frames having laid back “Slack” frame angles that would prevail into the 1950s.

Early frames were a hodge-podge of tubes of various shapes and sizes. The bicycle soon became mass-produced, which lead to it becoming an affordable means of transport for the working classes. Prior to that the only personal form of transport was a horse,

Mass production also lead to standard-ization and simplification of design. The chain itself is still half an inch pitch today the whole world over, even though most countries use the metric system.

Wheel sizes became standardized, and the frame design became the simple straight tube, diamond design, that we are all so familiar with.

Most of these standardizations came within the first ten years into the early 1900s. Tube sizes, 1 ¼ Head tube, 1 1/8th. Down and seat tube, 1-inch top tube. Most countries in the world including Italy, use these same Imperial size tubes. Hand brazed, lugged steel frames were, for the most part, the norm throughout this period.

It soon became obvious that frames would have to be different sizes to accommodate different size people, and the level top tube being parallel to the wheel centers, made it a point of reference, for the framebuilder to easily design and build a frame of any size.

The front fork being the same height for any frame, the position of the bottom head lug, and the length of the head tube is easy to arrive at, and head and seat angles are measured from horizontal top tube.

The advantage for the customer was, once he had established a size of frame that suited him, he could buy another of any make in that size, and it would fit.

Plus, the handlebars would be the correct height in relation to the saddle. No one spoke of handlebar drop.

When I left England in the late 1970s, my customers were almost exclusively amateur racing cyclists, their bikes all had the same componentry. Campagnolo Group, Cinelli handlebars and stem. Christophe toe clips, Binda laminated toe-straps. Tubular tires, and usually Mavic rims. Frames were either by a local builder like me, and therefore varied from one area to another.

If the frame was not by a local builder, it was by one of the larger English builders. Holdsworth, Mercian, Jack Taylor. Italian frames were not big in England at the time.  They were expensive compared to the UK built frames.

When the US Bike Boom happened in the 1970s English framebuilders, even the larger ones could not supply the demand, and they lost out to the Italian companies that  were larger, as they had been supplying most of the continent of Europe for years.

By moving to America, I was able to compete for a small niche of the market, but when the second bike boom hit, namely the Mountain Bike craze. Only a few high-end established mountain bike specialists were able to take advantage of their particular niche. The rest was taken over by companies like Giant, who found by building frames with sloping top tubes, they were able to build less sizes.

Above illusrates the evolution from the "One size fits all" BMX Bike, to the limited size MTB and Road Bike.

When this look became the norm, it made its way to road bikes, and by then carbon fiber was taking over from steel. Lugged steel had a good run, and I am proud to have been around at the end of that era.

The only other products I can think of that are made by craftsmen and remain the same year after year, are musical instruments. Everything else, including bicycles are now the same as any other consumer product that can become obsolete at the whim of the manufacturer.  

The bicycle, and in particular the lugged steel racing bike, took about ten years to establish standard designs and practices that would last for another 90 years. Towards the end changes in componentry came at a fast pace, (Index shifting, clipless pedals, etc.) culminating in the demise of the frame itself, which is fitting because after all the frame is the heart and soul of the bicycle.

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The ideal handling bicycle

Back in the early days of my framebuilding career, mostly in the 1960s. I was experimenting with head angles, fork rake, and trail.

It was in the days before electronic calculators, and computers, so I kept track of my progress with a graph drawn by hand on squared graph paper.

It looked something like the graph above, only it would have been in inches rather than centimeters. Today there are online trail calculators available.

Trail not only gives a bike stability and keeps it tracking on a straight line, but also gives it self-steering qualities.

When you lean into a corner, the bike will for the most part steer itself around the bend.

Because the bike and rider are leaning, the rider’s weight is being pushed outwards by centrifugal force.

However, there is an optimum amount of lean, too much and the bike will slide out from under the rider.

Therefore, there is an optimum trail, if a certain amount of trail is good, more trail is not necessarily better.

The amount of trail is not the same throughout a range of different head angles. The steeper the head angle the more sensitive the steering, therefore less trail is needed to have the same effect as it would on a bike with a shallower head angle.

In time I found there was an “Optimum Handling” line that I could draw on my graph, that would show me the fork rake needed for a given head angle.

Reading vertically down from where the fork rake line crosses the head angle line shows the amount of trail. As you will see, steeper angles, less trail, shallower angles, more.

The example shown 73-degree head, 35 mm. fork offset, and 67.3 mm. of trail, was my standard road geometry on the John Howard, Fuso, and Recherche frames I built.

I would build a track bike with a steeper head angle (75 degrees, 25 mm. rake.) making for  more sensitive steering because it is designed to be ridden on a banked velodrome.

The banking has the effect of riding in a straight line, not cornering like a road bike. The rider needs a bike that he can physically steer around an opponent in a quick move.

Also, in the event of another rider falling in front of him, he needs to be able to change direction in an instant. This was also my thinking, when I built a criterium frame with a 74-degree head, and 30 mm. of fork rake.

However, my standard road geometry gave this same ability to lean into a corner, let the bike take you round, but if you needed to correct your line, or steer around an obstruction, you can physically steer the bike by turning the bars, and pointing the bike in the direction you need to go.

I have said before, my bikes had a little more trail than most others built back when I was building, and more than on bikes produced today. That is not to say I am right, and all others are wrong, it is just my design philosophy is different.

The handling qualities of a bike do not depend on the steering geometry alone, it is the design of the whole frame, weight distribution, etc., etc.

When I recently rode a carbon-fiber framed bike, it felt okay, but the steering was different. Not bad, nothing I could put my finger on, or nothing that I could not get used to, given time.

My philosophy has always been, build a good handling bike, put a novice on that bike and he becomes an adequate bike handler. Put an experienced bike rider on the same bike and he becomes a brilliant bike handler.

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