I'm shopping online for some new tires, and see that some models are sorted by folding and wire beads? What exactly does this mean, and do I need a special rim to support them?
Folding versus wire refers to the material within the bead or 'edge' of each side of the tire. Foldable bead tires use kevlar in most cases (I think) and tires with each type are entirely compatible with the rim size that the tire is designed for (in the absence of a manufacturing defect). Folding bead tires have a few advantages (in my opinion):
- Somewhat lighter
- Easier to store (can be refolded by flattening the tire and folding it into a bundle)
- Bead has more stretch to it, so mounting the tire is usually less difficult
For these advantages, you will probably pay more for a foldable bead tire when a tire model includes both options. Also, wire bead's also appear more often as the OEM tires on lower end bikes.
Sheldon Brown can show you how to fold a wire bead tire.
Grab the tire at 10 & 2 O'Clock and overlap your hands until you have an uneven-size figure eight. Then just grasp the large loop of the figure eight, twist and push it towards the middle of the eight until you have three loops. Just tie it up with a strap and toss it into a bag.