the extra weight of folding bikes
Dollar for dollar, quality for quality, where do you guys suppose the extra weight of folding bikes comes from?
From what I can tell there are probably 4 main areas where folding bikes might be significantly heavier than nonfolders:
1. Solitary main tubes with hinges. Strength for strength the monotube construction is itself probably heavier than a triangulated design. The beefed up hinges must add some weight too.
2. Long folding handlebar posts. Flexible handlebars is one of the most common complaints of folding bikes and many folders compensate with oversized posts and beefier hinges. The Swift (one of the lightest stiffest folders around) notably sidesteps the entire hinge problem by simply not folding its handlebar post at all.
3. Long oversized seat posts.
4. Wheels. Although these should really be lighter than the usual large wheel formats, the kids and BMX markets combined with the commuter demographic seem to skew the availability of rims, tires, etc towards being heavy and overbuilt.
How is the extra weight typically distributed across these categories? In other words, how does a typical folding bike frame weigh compare to a typical diamond frame, a typical folding bike seat post compared to a typical diamond frame seat post, etc, etc?