Making the seat was a major challenge, as there is some complex bending to be done. However, this went more easily than I anticipated, then the challenge was to upholster it well enough that it didn't look like a real amateur job.

I must have succeeded, because on a club ride I was asked if the bike I was riding was the one I was going to clone.  It was the clone!

How does it ride?  So far, great!, but I've only put about 165km on it at time of writing.  Those that have tried it have loved the handling, and it's just as fast.

I've recently made a new seat for it out of fibreglass to get the weight down a little (my copy of the original seat was very comfortable, but very heavy as I used steel tube)  The new seat weighs about 1kg and is very comfortable when properly padded

Steps for the seat:

• Using a hot air gun, mould a sheet of coroplast to the shape required for the seat. 
• Lay up 3 layers of glass mat with as little epoxy resin as possible on the corplast and let it harden then separate and trim the fibreglass to size.
• Take 2 strips of 1/2 inch blue styropam and lay up as stiffeners, glue them onto the back of the seat with epoxy and when attached, round off the back of the foam.
• Lay up 2 layers of fibreglass/epoxy over the entire back of the seat, assuring that you follow the contours of the styrofoam.
• Add extra layers of glass at the points where you are mounting the seat.
• Make mounts (steel)
• Cover the flat part of the seat with 1/4 inch Plastazote, then 1 inch air conditioner foam.

Cost?  About $AUD300, thanks to various cheap parts from Bicycle Recycle, the donation of a 20-inch front rim (and a lot of great advice) from Alan B.

Some compromises had to be made in the build process due to materials availability.  I used the original 26 inch front forks but cut them down to 20 inch size.  Just re-welding the wheel mounts on the shortened forks led to too much trail and poor handling, so BMX-style extender plates were welded to the front of the forks.  I substituted tube guides for the rollers in the chain path, and this turned out to work great - I may even retrofit them to the original.  The clone uses non-indexed gear shifters.  I just could not get the original bike's indexed shifters to work reliably on the rear derailleur, probably due to friction and stretch in the long cable run.  A non-indexed shift lever made the problems disappear like magic.  The handlebar riser doesn't have the nice curve of the original.  It's made out of the seat upright tube from the original bike welded to the originals (cut down) handlebars. 

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