are six and a half billion souls on this planet and counting. There are
not enough materials and energy for everyone to live as the
developed world does now and many agree that we need to change our
of the biggest problems is the automobile. It not only pollutes but is
believed to contribute to climate change. Many of the alternatives now
being proposed, like electric cars, merely transfer the problem from
road to power station. A popular saying from over forty years ago puts
it in a nutshell :
Everything is connected to everything elseIn
the third world bicycles are a vital means of transport. In the
developed they are used mostly for sport and fitness .
However there are many, including the writer, who believe that the
re-introduction of cycling would benefit society. People would be
healthier and the death of local community might be arrested.Pedalling
is the most efficient way ever devised for people to produce
sustained power. But is the ordinary bicycle the best way of
using this power?
Everything has got to go somewhere
There is no such thing as a free lunch
biggest problem for a vehicle moving at speed is air resistance, which
is why streamlining is employed..
The upright bicycle has a large frontal area but by lying down in the
'recumbent' position this area is reduced and the machine is
easier to pedal. This was demonstrated in 1933 by Francis Faure
breaking the world speed record. (Unfortunately the World Cycle
Union then banned recumbents from competing and this set back development).Things
got going again in the seventies and today there is a wide selection
available of tested vehicles. Some builders put fairings on their
machines to make them go even faster : the current world speed record is 82
idea of pedalling extended to other forms of transport. It was found
that boats could be pedalled twice as fast as they could be rowed - in
fact fast enough to rise up on hydrofoils. Some boats have been
pedalled over the Atlantic. Others constructed aeroplanes, to show that
humans really could fly. Since most, but not all, of these vehicles use pedalling
exclusively they are usually referred to as 'human powered vehicles' or
most things the design of a recumbent is a trade off. In the case of a
bicycle the front wheel has to miss the pedals : either putting it
in front, thus producing a long wheelbase (lwb) suitable for cruising; or
putting it under the knees, the short wheelbase (swb) being better
adapted to nipping around congested areas.
well known by anyone who has ever ridden one that upright tricycles are
not stable because the centre of gravity is too high and the rider
cannot lean into corners as on a bicycle. The recumbent tricycle
reduces these problems considerably. There are two configurations : 'tadpole' with two wheels at
the front, and 'delta', with two wheels at the back; In addition to these mainstrean recumbents many other
designs and combinations will be found on the net : front
wheel drive, tilting trikes, and the 'sociable'. Many build their own
machines , often using recycled parts.
Ice and Snow
cold climate presents a variety of surface conditions. Cycling through
wet snow is like cycling through mud. Cycling on ice requires
knobbly tyres or studs. Nevertheless winter cycling is alive and
well and some enthusiasts race on ice.The idea of the 'ice bike'
goes back a long way and many patents have been taken out on a variety
of spiked tyres or studded belts :
However not much attention
seems to have been paid to skis and I wondered why not. I lashed
a pair of skis to the front of a bike and found that I could push
myself along OK, even though most of the weight fell on the back wheel.
But the upright bike provided no convenient point of attachment for the
skis to be mounted further back. So I decided to make a lwb recumbent
for further experiment.
line with the philosophy of re-cycling I cut up a kids mountain
bike. Normally brazing is considered the best route for a home builder,
but I found myself in a small but clean flat with few tools, so I
used pine, glassfibre, and epoxy to make a beam connecting the
headset and rear triangle. It is a very easy method. I used an old
camping chair for the seat.
that some form of steering would be necessary, I also experimented with flexible linkages. Finally
handlebars were made adjustable in the fore and aft direction to accomodate
alterations in the vehicle's centre of gravity :
Normally February is the coldest time of the year and there is thick
layer of snow and ice here. This year February has been very strange
and as I write spring flowers are emerging. Without carting this
contraption further north there was a single window of opportunity to
test it before the brief snowfall melted. A very brief clip of the test is here :
had intended to experiment further but it looks like my chances
are limited this winter. These are the things that can be
the main problem is drive. The wheel I used was too small and not
'knobbly' enough : some form of belt, or lightweight
drum mimicking ski poles, would seem to be a better
alternative. Then the driver's weight could be placed more nearly over the centre of the skis.
the steering arrangement needs to be properly worked out. Ski
poles/'handlebars' can themselves be used for serious
braking by thrusting them into the snow
3) the skis I used are too small for soft snow conditions. Today
most people ski in tracks for fitness and the width of
modern skis has shrunk to 4 cm. But the remains of skis (some of
them thousands of years old) have been excavated which are
very much larger : some of them three metres in length and 14 cm.
from birch or pine, evidently to handle virgin snow. The
'snowshoe ' below from 420 BC gives an idea how delicate these things
It is interesting
to speculate what a properly designed pedal-powered, lightweight,
vehicle using such skis might be capable of. Perhaps others
might be interested in experimenting further? ( I should think that
kids might like the idea.