+1 for Alan's method.
Using a good epoxy makes for a good bond, the quick the cure time of epoxy the more brittle the bond will be so i always go for a good quality epoxy and usually long cure 24hr like Araldite Precision, this gives a good working time and also allows for clean up time.
I usually go for a belt and braces method by drilling and installing an M3x10 button head bolt through the support end and carbon tube. This is not required but is just something i prefer to do. It is simple to do using the holes in the plastic support ends as a guide, making sure the ends are aligned perfectly before drilling with a 2.5mm drill bit. Once everything is done I rough up the ends of the carbon to be installed in the plastic support ends with sand paper, this gives the epoxy something to bite into and creates a good bond once cured. Clean the carbon with alcohol or cleaning spirit then apply adhesive into the plastic end and also on the carbon tube, install the carbon tube into the plastic end and using a toothpick to locate the hole then secure with a M3x10 button head bolt. Clean up all excess epoxy and repeat the process for remaining ends.
Hope this helps,
Ross
