Cutting Carbon Fiber Handlebars
From Pvdwiki
Wrap with tape to keep the fibres from splitting.
Mark the cut
A thin fibre saw is probably the best way to actually cut the woven carbon bar, but lacking one of those, use a power band saw with a very fine blade. A hacksaw will work, but be very very careful. The goal is to not split the lamnination.
Nasty.
Clean up the end on a belt sander.
Clean.
Done.