Undercarriage starting to tingle, in a bad way, during a long right It might be time for a new saddle, like the Selle SMP Dynamic Saddle. It's all about reducing pressure in key sensitive zones, with a dramatically dropped nose to provide a flat base without exerting excess stress on your down belows. There's also an extra large central channel to relieve pressure on soft tissue areas, and the back of saddle is raised to help you achieve an efficient pedaling position without the pain of squashed sit bones. Selle built the Dynamic's shell from a composite of nylon and carbon, which gives you a firm pedaling platform that won't transmit excessive road vibrations into your rear. The cushion comes from the foam elastomer padding, which is firm but forgiving, and the exterior of the saddle is either leather or Lorica, depending on color. Both are durable and smooth, and there's no weight difference to speak of. Finally, the Dynamic clamps to your seatpost via rugged stainless steel rails, so you can ride as hard as you can with no slippage or bending.