Bickerton 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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sts

Click all thumbnails to enlarge

trailer.02s

 

Gooseneck Detail Above

dtrs

    Stacked for Transparent Bagging at   Airline Sum of Dimensions=60”

 

 

Rear Detail, Right Backpedal Chainwheel

                    Ratchet to centrepull brake

 

 

 

 

Diagonally Armpower chain, sprocket 

                                 &return bungey