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Friday
Jul212006

What does the length of your forearm and the price of fish have to do with stem length?


This method of determining handlebar stem length has been around for ever. My cycling experience dates back over 55 years and it was practiced then; actually it is not a bad guide and works for most people. Place your elbow against the nose of your saddle and if your finger tips do not fit behind the handle bars as shown above, then your stem is probably too short. If the bars are more than 2cm. away from the finger tips your stem maybe too long.

When I was racing I used a stem that placed my finger tips one centimeter from the bars; now as a mild concession to my aging body I’m using a stem a centimeter shorter. If you are wondering as I did for many years what the length of a persons forearm has to do with stem length? I will explain.

When I am determining frame size I take into account three body measurements:
1. Inside leg length (Often referred to as inseam.) measured crotch to floor without shoes.
2. Overall height.
3. Shoe size. (Length of foot.)
I do not require body length because I have overall height minus inseam. I do not require arm length because this is relevant to leg length and foot length combined.

Human bodies although all different do generally follow certain rules of nature. We have the same basic design and structure as most other animals on this planet except we walk on our hind legs while most others walk on all four. So it follows a person with long legs will also have long arms; short legs, short arms.

Four legged animals generally walk on their toes (and finger tips) whereas we stand and walk on our heels. So some people have a long body, but short legs and it is not unusual for a person with this build to have longer feet, and also longer arms. The long arms are not out of proportion if you consider the leg length is a combination of inseam plus the length of foot.

When pedaling a bicycle the toe is pointing downward at the bottom of the pedal stroke so the foot becomes an extension of the leg; which is why it has to be taken into consideration when determining frame size. The person with short legs, long feet needs a larger frame than their inseam alone would suggest. The larger frame with its proportionally longer top tube will also accommodate this rider’s longer body and arms

The length of the forearm is proportionate in length to the length of the foot; take one of your shoes and hold it against your forearm and you will see it is the same length as the distance from your elbow to your wrist. In other words the big bones in your forearm are the same length as your foot.

So assuming you are on the right size frame and your seat is set at the correct height; then chances are if you have very long feet then you will have a short inseam and a long body.

Because you have long feet you also have a long forearm and if you do this little elbow against the saddle trick it will show you need a long handlebar stem which will be right for your long body and arms.

A person with very long legs for their height will also have long arms but will have a short body and small feet relative to their height. Small feet mean short forearm and a shorter stem which will be right for their short body. Because this rider has long legs his saddle will be set high making a greater distance from the seat to the bars; this will accommodate his long arms.

There is another method for determining stem length which states: “A rider seated with their hands on the drops of the bars, will have the front hub obscured from view by the handlebars.”

This works in the same way; longer body calls for a longer stem and vice-versa. The only thing is that this method could be affected by the head angle of the frame and the length of fork rake. I prefer the length of forearm method because it is simpler. It works for most people but there is a small percentage that it will not. I always say if you are comfortable and happy with your current position, don’t change it. Go by the old “If it ain’t broke” adage.

And what does this all have to do with the price of fish? Nothing at all, but it got your attention.

Monday
Jul172006

On the road again


I finally got my bike put together at took my first ride in at least fifteen years; I rode for exactly an hour at a pretty brisk pace and it felt good. I could have gone further but decided not to do too much on the first day.

I have had the frame for about six weeks now; a 52 cm. Fuso that I built in 1986. It had a brand new paint job in the 1990s and the previous owner never built it up after that. Very tastefully finished in a royal blue with understated black decals; I bought some Vittoria Corsa tubulars with blue sidewalls and found some blue and black handlebar tape. Black brake cable housing finished the job.

The components are all Campagnolo SR from the 1980s; the hold up in getting it finished was in finding a bottom bracket spindle the right length. It finally arrived on Friday and I put the whole thing together over the weekend. Also arriving on Friday was pretty rare NOS Super Record 48 tooth chainring that I had found on eBay. This gives me a much more usable range of gears with a six speed 13 – 18 freewheel.

Old bikes are like old cars; you can work on them yourself. I love the simplicity of down tube mounted friction gear levers. I read a statement by someone who said “Indexed shifting is like frets on a fiddle.” I’m inclined to agree. I adjusted the gears in the house expecting to have to do some final adjustments as I rode it, but it all worked perfectly.

Don’t get me wrong; I’m not knocking the new stuff and if you are racing the bar mounted shifters are probably a huge advantage. But for someone like me who’s just riding for pleasure and exercise; why get complicated?

I love the beautiful lines of the older bikes; they look so flimsy with the thin tubes and rims and yet are so very strong. It is what started the whole love affair in the first place.

I will admit that I do like the new clothing; the padded shorts instead of chamois leather insert that was a pain to wash and dry. (Of course you could clean your windows with it.) I haven’t gone clipless yet but probably will in a few weeks when I have got used to riding again.

And the helmets; they finally got that right. Do you remember back in the late 1970s early 1980s when the Bell helmets were the thing? Looked like a fucking great white mushroom stuck on your head. These new helmets actually look cool so I am wearing one for the first time.

Alright so I’m a poser; what can I tell you? But you probably figured that out when I said I’d bought blue tires to match my blue frame.

Monday
Jul102006

Get out and ride it: It's what they're built for


Mark Rosenberg emailed me pictures of a 50 cm. Fuso he recently picked up on eBay. The previous owner had peeled the decals off for whatever reason so it was ugly, but this did mean he got it for a pretty low price. (See below.)


Mark opted to go for a $100 red powder coat paint job which only took a week to do; he built it up with parts he already had, and he was on the road. He reported to me that the bike was a nice ride, great handling, and quick, very stable. He added, great shock absorption, can't figure that one out.  A good steel frame is like a very stiff spring, so it will absorb road shocks. At the same time when the rider makes a sudden effort it will give a little but then immediately transfer that energy to the back wheel.

It pleases me when I see one of my frames with the original paint and has been cared for. It pleases me when someone spends a good deal of money to restore a frame to its original glory. But I think what gives me the most satisfaction is when someone like Mark just rides it. It is what the frames were built for; the beauty is in the way the bike rides and handles, not just in aesthetics.

See more pictures of the bike here:

Friday
Jul072006

The Number 10 Fuso Just Surfaced


The other day I received an email from someone who had just bought one of my bikes. It was a 53 cm. Fuso (Pictured above.) and although the buyer had not heard of the name before he worked in a bike store and knew enough about bikes to know that this was a quality product and he got it for a bargain price. “Almost brand new, hardly ridden.” Was his comment.

After buying the bike he did a Google search and found my website which led to his contacting me. The thing I found interesting was the serial number 010; yes this was the 10th Fuso built and by far the lowest number Fuso I have heard about outside of the number 001.

The number one Fuso was a 58 cm. and was used for display at a trade show when I introduced the brand in 1984. After the show I gave the bike to my friend David Ball from San Luis Obispo, California in exchange for some photography work he had done for me. Several years later David sold the bike to the owner of a local bike store, and as far as I know he still owns the bike even though he has since sold the store.

The Fuso was built in batches of five frames at a time; so the first five were 58 cm. and now it seems the second batch of five were 53 cm. I have considered starting an owner’s register where frame serial numbers would be registered against the current owner’s name. But with close to 3,000 Fuso frames built between 1984 and 1993 the number of owners in contact with me is less than 200, and that’s for all frames built, not just Fusos; so it hardly seems worth it. There would be a lot of gaps in the register; a lot of frames un-registered.

I see Fuso bikes and frames for sale on eBay all the time; in fact is rare for a period of more than a week to go by where there is not one for sale. I always monitor these sales and keep track of prices for my own interest even though I have no part of these sales. Once a bike is sold rarely do I hear of it again.

So it seems the Fuso and the other brands I made are still one of the best kept secrets around. With only 200 owners that I know of means there are several thousand others out there; many of them sitting in garages and basements and can still be picked up at bargain prices because the owners don’t know what they have.

Friday
Jun302006

Squirrelly

The word sometimes used to describe a rider’s style but more often it is used to describe the way a bike feels or handles.

Typically a bicycle that is “squirrelly” has a steep head angle and will deviate from a straight line at the slightest movement. Some people like the lively feel of a bike like this and I often hear quotes like, “People who call a bike squirrelly don’t know how to ride a bike.”

Agreed if you put a novice on such a bike he is a danger to himself and others; put an expert on the same bike and he can ride it safely. However take the same novice and put him in a bike that handles well and is easy to ride and he rides safely, and the expert on the same bike becomes a brilliant bike handler.

Why build a bike with a steep head angle anyway? Track bikes designed to be ridden on a banked velodrome have steeper head angles, because it is necessary to be able to change direction quickly to dart around an opponent, but the banked track has the effect of the rider traveling in a continuous straight line. At speed the rider is still theoretically 90 degrees to the track surface, and actually centrifugal force is pushing him down on the surface making it harder to deviate from a straight line. Hence the steep head angle to compensate.

Steep head angles on road bikes were in vogue in the mid 1970s and some builders carried it on into the 1980s. I never followed this trend and for a while was I was out of step with most other builders. Let me take you back to look at the history of bicycle design and to explain why this happened. In the 1940s an 1950s when I started riding the standard road geometry was a 71 seat angle, with a 73 head angle. The shallow 71 seat angle can be traced all the way back fifty years earlier to the Ordinary or Penny Farthing.

Early “Safety” or conventional design bikes as we think of them today also had shallow head angles, but by the 1940s it had been established that 73 degrees was the ideal head angle. I happen to believe that is still true today; however bikes of the 40s and 50s had 3 inches or more of fork rake. There was a theory back then that the steering axis, a line drawn through the head tube, reached the ground at the point where the wheel contacted the ground.

In other words there was zero trail; the theory was if you had trail the steering would be sluggish and heavy. The 71/73 angle design made it convenient for framebuilders to make frames in various sizes. With the head and seat angle going away from each other as the frame got bigger (Taller) so did the top tube become longer. The heavy steel cast lugs used back then gave little scope to build frames with different angles.

Moving on to the 1960s there was a huge slump in bicycle sales world-wide as economies boomed and in many places working class people were buying cars for the first time. The cost of a frame hardly rose from the late 1950s to the early 1970s even though earnings and the price of everything else had.

Framebuilders had to look for ways to cut corners and build frames in less time. No braze-ons was one cut back; and another was the parallel angle frame. First 72 degrees parallel because riders were not ready to jump from 71 to 73, but in a short time 73 seat and 73 head became the norm.

Framebuilders were using jigs for the first time for speedy assembly and the parallel design made it possible to make a simple fixed jig. Tubes were pre-mitered all the same length and to build various sizes of frames they simply raised or lowered the top tube. You could have any length top tube as long as it was 22 1/2 inches. Rather like Henry Ford; any color as long as it’s black.

By this time the fork rake had become a little shorter, and to have trail was considered okay, overall wheelbases had also shortened and everyone realized that these bikes were a lot livelier than the bikes of the 1950s. By the 1970s the framebuilder’s lot had improved with frame prices starting to catch up with the rest of the economy; helped along by a bike boom starting in America.

Remember back in the 1950s with the seat angle 2 degrees shallower than the head angle and how it made it convenient to build various size frames with varying top tube lengths. Nobody wanted to go back to 71 seat angles so frames began to appear with 73 seat and 75 head angle. Riders also discovered that these steeper head bikes felt livelier, especially when you got out of the saddle to sprint or climb.

About this time I was doing my own experimenting with frame design and I realized that it was not the steeper head angle that gave the bike its lively feel, but in making the head steeper they had moved the front wheel back directly under the handlebars. When a rider gets out of the saddle to sprint or, climb the bike is going to sway from side to side whether intentionally or unintentionally.

With the handlebars directly over the point where the front wheel contacts the road the bike can swing from side to side keeping in the front wheel in the same straight ahead plane. I had remembered back in the 1950s with those long fork rakes and short handlebar stems; the bars were way back behind the wheel’s point of contact. When you got out of the saddle the bike felt sluggish and heavy. I named it “The wheelbarrow effect.”

As the bike swayed from side to side the front wheel was turning to the left and right, but the gyroscopic action of the spinning wheel was trying to keep the bike straight; you had two forces fighting each other. To demonstrate this to yourself place the end of a straight edge on the ground and hold it 90 degrees to the ground. Swing the top of the straight edge side to side and you will see it moves in the same plane. Now hold the straight edge at an angle to the ground and move from side to side; you will see the top end where your hand is swings in an arch. If this were your bike you would be turning the front wheel as you swayed.

I never liked the twitchiness of the steeper head so I stuck with the 73 degree head angle and to get the handlebars over the front wheel I did two things. I shortened the fork rake; this actually gave my bikes a little more trail than average and made the bike very stable and gave it certain self steering qualities. The other thing I did was shorten the top tube and use a longer stem. The result was a bike that felt just as lively but without the inherent twitchiness. A rider’s weight is mostly in his shoulders and upper body so by pushing the rider forward as I did I moved the mass forward greatly improving the bike’s handling especially when cornering and descending at speed.

Most frames built today have a head angles around 73 degrees; a degree either way is no big deal. It is when a head angle gets to be 75, 76 or steeper would I consider it steep. So to sum up; what makes a bike squirrelly? A steeper head angle has less resistance to turning, so any slight movement of the bike will cause it to deviate from a straight line. Also steeper head angle means less trail which is the castor action that helps to keep a bike tracking straight.