BILL BOSTON CYCLES
BILL BOSTON CYCLES
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Those bikes with small front wheels
In
late 1974, a friend called asking to stop by. He and his girl friend were in
college in Montana. Alice had been having problems riding a Gitane mixte on
their club rides. She was a good rider but, at 100 lbs, was at a big
disadvantage pedaling a 40-pound bike up hills. They were hoping I could build
Alice something lighter so she could ride at the front of the pack. When
they arrived at the shop, I was surprised to see that Alice was barely over 5
feet tall. I knew immediately that this was going to be a major design
challenge. We used my road bike and a stack of blocks to establish a maximum
stand-over height of 28 inches. And, observing Alice on her bike, I quickly saw
that the effective top tube length was far in excess of what she needed. Then
we worked at deriving a top tube length that was appropriate. If memory serves,
we used a spare set of bars, which Alice held while sitting on my bike. As Ted
held up the bike, Alice moved the bars trying to find a position that felt and
looked right. Then I measured how far the loose bars were behind the fixed ones
on the bike. From that we decided a 19 inch top tube with an 8 cm stem would be
good. We
discussed crank length and decided to try shorter ones than the 170 mm length
that she was using. We agreed that 155 mm would be a good starting point and
that we could adjust the gearing downward to compensate for the loss in
leverage. We believed Alice would be able to increase her cadence more than
enough to maintain the speeds she was used to. However, I knew I still had many
problems to solve and told them that I would call in a couple of days when I had
some solutions. The
biggest problem was to get the top tube lower than 30 inches from the ground,
which is the lowest that can be built while maintaining a head tube. I decided
to make a scale drawing of the bike – something I had not done in years. Ok,
I know, you are asking yourselves how could I build bikes for more than two
years without making drawings. The answer was simple. When I started building
bikes, some hot new technology arrived from Hewlett Packard in the form of a
scientific calculator. With that I could make faster calculations and get more
accurate dimensions than I could by hand. Back
to the story. I laid out the bottom bracket, the seat tube, the top tube, and a
line to represent the head tube. I kept looking at the drawing and finally
realized there was no way I was going to get a 27 inch wheel in there. Even if I
played around with the head tube angle and rake, there just was not enough room
for toe clip clearance (of course now it would just be pedal clearance).
Suddenly, I knew how Archimedes felt when his bathtub overflowed. I had been
trying to make the bike and rider fit the components.
Clearly that was not going to work. After
taking more measurements, I found I did have sufficient room for a 24 inch wheel
in the front. I cleaned up the drawing and excitedly called Alice and Ted and
told them that I had a solution I thought would work. At
first Alice was disconcerted with the design, as she thought two different wheel
sizes would look strange. And you know, some people still have that criticism
today of Georgena Terry’s small bikes. However, I was so confident in my
sizing system and the design that I offered to build another bike for free if
she did not like it. The bike was ready at the end of March 1975. I soon received a letter telling me how much Alice was enjoying her new bike and that she was always near the front of the pack on club rides, particularly on the climbs. Of course the fact that the bike came in at about 18.5 pounds didn’t hurt, but Alice will tell you that the improvement in fit had a lot to do with her improved performance as well. And of course there are hundreds of riders using Georgena Terry’s small front wheel bikes today who will tell you the same thing. |
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Copyright © 2003 BILL BOSTON CYCLES
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