Again, pardon my ignorance, but is a quill to ahead adapter the same as a steerer extender?
I've got some thread less forks which are too short for my head tube, is there anyway to extend them or run safely? thread less stem stack will work with them, it will leave 5-6mm only after. They have an alloy steerer.
Answer is no, you need one of these;
http://static.bike-components.de/cache/BBB-Extender-BHP-22-Adapter-Ahead-schwarz-1-1-8-2553142cc74e7a8a2a528cf3d18e4530.jpeg