16" wheel folding bikes, such as the Dahon Curve and Downtube mini have small wheelbases. This is nice for tight city riding ( allowing for fast turns ). However these bikes are not stable at high speeds. A longer wheelbase will bring stability at speed, and will increase the virtual top tube length to allow riders to stretch out into a more comfortable riding position.

All of our new 20" wheel bikes have extra long wheelbases to allow for more stability at speeds.