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Strong
controllable braking independent of hand position/signalling/cargo
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Ideal for the rear stirrup brake of traditional
English/Indian/Chinese bikes
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Also very simple
for cable braking and rear derailleur gearing
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2 or 3 moving parts very
simple to make
FARTHING PENNY Bouquet Cargo Bicycle
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Carries a 20L bucket of
cargo with multi- pocket organiser
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Small bike handling and
manoeuvrability with big bike power
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Silent, powerful and
jam-free backpedal braking with derailleur gearing
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Sit up & Beg
handlebars provide elbow rests for Praying extension
This design arose
from use of standard bucket and bucket organiser to transport cargo (mainly
groceries) in living without a car. Panniers require extensive frames and
support points to keep them out of the spokes, complicating removal. In the
front their weight and volume capacity is limited by turning with the
wheel. Rear panniers or racks do not allow monitoring the contents when
riding and add extra spoke-breaking load to the rear wheel which already
bears 110 lbs of a 175 lb rider.
Backpacks have a particularly high center of gravity again too far
back and exacerbate the differential cooling problem that leads to a wet
and clammy back yet a frozen front. A cheaper system is to take advantage
of the ubiquitous 5 gallon bucket and the cheap pail organisers that are
mass produced for the building trades. These hang over the bucket rim with
numerous pockets on the inside and outside. Instead of adding wind
resistance, a front mounting provides a bit of a round entry fairing to the
body behind. The maximum 45 lbs
of 5 gal bucket full of liquid then
evens the weight on each wheels at 100lbs
for a 175 lb adult.
At first a bucket
was suspended inside the “praying” handlebars of a standard 10 speed but a
full load then affected the steering a bit severely. So it was clamped in
front of the steering tube to the frame with a quick release lever whilst
straight handlebars on a simple gooseneck gave sufficient steering movement
behind it. In fact the movement was
often annoyingly more restricted by the near interference of the toe in
front of the pedal hitting the back of the front wheel. This begs for a
smaller front wheel which would also lower the weight of the cargo and the
top of the bucket below the arc of the handlebars. The grocery delivery and
Paschley Post Office bikes in the UK have slightly smaller front wheels
under their trays attached to the frame
The stability and control of a bicycle are largely governed by the
steering front wheel, and folding bicycles have shown that a small front
wheel has very good balance as well as high manoeuvrability.
But the standard
rear frame is a lighter way to stiffly support the seat and a fullsize rear
wheel allows light yet high derailleur gearing. So the idea was to just
change the frame ahead of the seat-tube to allow a small front wheel but to
keep it and the handlebars stiff.
Since the steering tube is parallel to the seat tube, the front end
can be lowered by parallel cutting the front and top tubes through their
lugs at the seat tube. Then the interchanged lug cuts fit well and weld
easily even with rods. Then another steering tube can be welded on top more
or less in the original location. Since these are the largest diameter
tubes in a standard frame this is far stiffer than a long gooseneck. A section of straight steel handlebar can
be welded in a cut in the fork tube to extend it inside the longer steering
tube. A bracket to hold the bottom lip of the bucket is welded to the
bottom of the steering tube just above the tire, and a semicircular bracket
welded from its middle from which straps encircle the bucket.
The prototype also
has backpedal braking with a silent ratchet on the chainwheel and a small
chain pulley on the same ratchet brake lever which causes top side slack
with the backpedalling (to allow forward pedalling and so brake release.)
The handlebars are an inverted “sit up and beg” so that there is a hollow
for the elbows to locate in when the forearms are resting on a delta “praying
tuck” extension.
ReCYCLE
Cargo Trailer
Compared to
car utility and boat trailers, bike 2 wheel trailers have a much narrower
wheelbase and less deadweight so it is
preferable to have the bottom at minimum ground clearance of say 4” ,
(the same as the pedal). Otherwise with the good inclined cornering of the
bike a heavy (and high) load can easily flip the trailer. Even with
inflated wheels the shock on rigid trailer (and bucket) cargo is fairly
high so a suspension is useful to reduce the noise of loose cargo and
possible damage.
Remarkably these
desiderata, rarely achieved in
custom trailers, can be met with a
compact trailer weighing only 18 lbs and made entirely of cycle
components. An old bike frame makes a lightweight
trailer skeleton with an offset rising arm for loose vertical bolting to
your bicycle for short loads. The seatstays are cut off and rewelded to the
bottom bracket lugs of the removed chainstays to form this triangulated
arm.
The trailer wheels
are 16” or 20” rear wheels with the axles replaced by pedal axles Make sure
you mount the wheels freewheel-side in, as they are dished, and mount the
lefthanded crank thread on the lefthand side. They are easily screwed onto
pedal cranks whose big ends are welded to the ends of (1" EMT
electrical conduit) tubing which passes through the head tube with a central locating pin.
This EMT is best slit lengthwise for torsional flexibility to give a
suspension to the extent the cranks are angled ahead. The cranks are
pointed up too to lower the frame below the wheel axles.
Multiple pin holes
in the frame allow adjusting the height and suspension effect between
straight ahead cranks for storage and max suspension for heavy fragile
loads to be cycled slowly to say 60 degree up cranks for light rugged loads
to be carried low and fast.
There are mainly
different styles of pedals. ˝” or 9/16” interthreads and outer . 5/16 or
.278”(24 tpi) threads. One piece
cranks are always ˝” and the right side often has a flaring at the axle
which is easy to weld to the EMT as is the big end of a standard
cranks. Front wheel axles are
5/16-24 so their threaded cones can used instead of the too-small pedal
outer cone on 5/16 pedal axle ends. The dirt cover can be pressed off and
replaced with a bigger one or the entire hub outer end covered.
A sleeve can drilled from 3/8 rear axle to
allow mounting the normal 3/8-24 thread rear cone on a .278” pedal. Chuck
the axle segment in a drill press and use a stationary center drill and
then H&J letter drills clamped in the table vice. Set those upright by
lightly chucking the wrong ends.
Tow-a-Bike to a Friend
This is an easy way to tow an empty
bicycle behind your bike, for instance to public transport to provide your
visitor with a bike. Basically the idea is to remove the front wheel of the
bike to be towed and carry it bolted on one side of your front fork. And
then mount the front fork of the rear bike over the ends of your rear axle
either directly or with some flat bar with holes for the axle and hose
clamps for the forks. The connection must be strong but allow the fork to
pivot to conform to bumps in the road. The empty rear bike will then tow
obediantly behind you with very little drag. The connection is not
strong or stiff enough to make this a tandem. Please don’t try
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