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Farthing Ha’Penny Portable Bouquet
Folding Bike 2012 (video)
Over the years an aluminum Bickerton
folding bicycle has been almost completely rebuilt in parallel with development
of the backpedal brake, cargo bucket and armpower. The original Bickerton
design suffered from overall flexibility, especially great weakness of the
steering fore and aft against only a quick release clamp. Security against
falling forwards is vastly improved with the strong positive fore and aft
lock, and the backwards pull of the bridle from the shockcord and the load
of turning the rear wheel. The
rowing stroke is actually greater than a fullsize Farthing Penny due to the small rear
wheel being further from the seat even if the armpower gear is lower.
The 1”x.78” steering tube was replaced by
stiffer and stronger aluminum pipe which at 1.06”x .83 fits inside standard
steel bearing cones replacing the plastic originals. The Bickerton
gooseneck is now compressed by the pipe nut, adding a pretension stiffness
through the bearings. The handlebars rotate in the gooseneck with a second
set of the same standard bearings. The locking pin is clearly visible
to check engagement. If the front wheel were increased to 16”, the
decreased handlebars would meet the rim in folding.
The bigger rear triangle is welded stiffer
with a rectangular seat-tube locking
the seat against twist. Instead of compromising the short chainstay with severe
bending and flattening (even more to make room for the backpedal brake) a piece of aluminum flat
1x.25” was bent instead with the end slotted for the heavy tightening
required at the rear axle. The larger 20” rear wheel has lighter derailleur
gearing than the original Sturmey Archer 16”. The handlebars of readily
available and solderable copper tubing, total weight is 25 lbs. These have
since been replaced with lighter stronger 7/8” aluminum “bimmy” tubing.
The Bickerton frame joint is retained but
without the hinges so the bike breaks down into front and rear halves which
can still be stacked to airline bag size despite the larger rear wheel.
With the backpedal brake and the shifter moved to the seatpost clamp there are
no Bowden cables complicating the separation. The shockcord front pulley is
easily unhooked as is the bridle wire.
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Click
all thumbnails to enlarge
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Gooseneck Detail Above
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Stacked for Transparent Bagging
at Airline Sum of Dimensions=60”
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Rear Detail, Right
Backpedal Chainwheel
Ratchet to centrepull
brake
Diagonally Armpower
chain, sprocket
&return bungey
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