Originally Posted by mingonn
Stelvios are a must then the seat if you don't mind a harsher ride. From then on it $$ per gram goes up, and up and up.
What amazes me is how much lighter comparable priced road bikes to folders. Bigger frame, longer spokes, bigger wheels, front deraileur, etc and they often weigh the same or less. Those hinges must be heavy.
It's all about stiffness. To get a decent ride a bike must not flex too much. A triangulated frame, like a standard bike, is very stiff. So you can use lighter weight materials and still get good stiffness. Most folding bikes use a single tube connecting the front end to the rear of the bike. To get good stiffness you need to make the tube pretty thick. That adds weight to the frame. The hinges will also add extra weight.