Triathlete Training Podcast: Triathlon, Ironman & Duathlon

Subscribe via iTunes Aerodynamics With David Ripley of Zipp In addition to working for Zipp, David is also a bike fitter and consultant for 51 Speed Shop. Topics discussed include: The Four restrictive properties working against you on the bike are: 1. Aerodynamics 2. Gravity 3. Drivetrain Friction 4. Road Friction 75-80% of aerodynamic drag comes from the body.  The wheels are the second greatest source of drag.  Components are next, and the frame is last.   Weight doesn't become a significant factor until the grade hits 6% for an extended period of time.  A good clincher and latex tube compared to a poor tire and a butyl tube can result in a 10-11 watt difference per tire.   He recommends air pressure of 100psi for a 150 pound rider on a tri bike on a smooth road.  On a rough road a slightly lower tire pressure is recommended.  Biggest bang for your buck in aerodynamics  Vibram Five Finger Shoes A 10 week study published in the July 2013 issue of Medicine & Science in Sports & Exercise compared tw