Take one Chinese carbon handlebar extender jobby off ebay

Dismantle, measure the carbon pole and cut in half

Cut majority of small ring away, leaving a wonky nut of sorts

Smooth off the cut ends

With a bit of luck the carbon pole should slide on nice and snug, with a tight fit at the wider clamp


The cheap clamps are a bit crap, I might try another wrap of tape or line the clamp with something else. The wonky nut could be replaced with a bit of half round timber, or sugru etc.
Thought I'd have a go for a laugh, i was never going to use the bar extender as it was