Most folding bicycles are intended for commuter and utility purposes, hence emphasize ruggedness, comfort and convenience over speed. A small number of high-end folding bikes are made for speed. In the interest of compact folding, certain trade-offs are common. Most folding bicycles use small (20 inches (51 cm) or less) diameter wheels. All else being equal, smaller diameter wheels give a rougher ride than larger wheels. Folding bicycles often have a shorter wheelbase, which also contributes to a rougher ride. To avoid losing any more comfort, narrow tires are rarer than for non folders. Suspension systems can be incorporated into the design of a bicycle to give a smoother ride. The suspension, however, will also absorb some of the pedaling energy that would otherwise be used to move the bicycle forward in a more rigid bicycle.[citation needed]
Folding bicycles often separate or fold in the middle of the frame, which, depending on the design, can weaken the frame and cause more energy-absorbing flexing. Many have elongated seatposts and stems. These longer components, which project above the frame like masts, experience greater bending stresses where they meet the frame, compared to the shorter components of regular bikes. There have been sporadic reports of failure in these components in online message forums[citation needed], and at least one recall due the failure of the steering mechanism.[citation needed] Folding bicycles necessarily have more parts, to allow folding and to lock the frame when unfolded. This results in a more complicated design, with more parts that can potentially fail.
