At Ti Cycles near Portland OR, they can custom fabricate things for you,,
Have an order in their Queue to replace the Al alloy folding mast from my Pocket Llama/..
they can do it in steel, powder coated or Ti..
Though they said the elasticity of a long Ti tube may not be as desirable steering
rather than under seat comfort...
Oversize tube diameters were used in that 1 prototype "Ultimate Folding Bike", to stiffen up some excessive flex.
with an intended 10K$ selling price..
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