Folding bicycles traditionally lack stiffness in the handlebar/stem (we call it a handlepost) assembly. Long, extended handleposts are long levers that exert a tremendous amount of force on frames, headsets and forks. Traditional bicycle technology wasn't designed for the handleposts found on folding bicycles so we developed new technology. Our patented Fusion technology, improves on the "threadless" stem of modern mountain bikes and blends frame, fork, and handlepost into a single integrated, immensely strong, structure. Fusion technology boosts front-end stiffness by more than 30% compared to traditional quill designs. Dahon patented technology.