For people with hearing loss, the sound signals from the inner ear to the brain will be weaker than normal, and it's possible that the brain amplifies these signals too much to compensate, resulting in hypersensitivity. However, this doesn't explain the cause in those with hyperacusis and no hearing loss.
Bicycle Valve Stem Types. There are three types of bicycle valve stems in use: Schrader, Presta and Woods/Dunlop. The Woods or Dunlop valve stem style is much more rare than the other two. Any wheel rim that fits a Schrader valve can also fit a Woods or Presta valve.
Inner-tubes are the inflatable parts between the tire and the metal parts of the wheel. They are invisible apart from their valves that protrude through the wheel-rims. There are three valve types in use; Schrader valves, Presta valves, and the lesser used Dunlop valves. Refer to the adjacent image for examples.